Hollow resin particles and use thereof

Abstract

Hollow resin particles according to an embodiment of the present invention comprise a shell part and a hollow portion that is surrounded by the shell part, said hollow resin particles having an average particle diameter of 0.1-1 μm. The proportion of the hollow resin particles that are coarse particles having a circularity of not less than 0.97 and a particle diameter of not less than 5 μm is less than 5% on a particle number basis.

Description

Hollow resin particles and their uses

[0001] The present invention relates to hollow resin particles and uses thereof.

[0002] In order to accommodate the high-frequency signals required for next-generation high-speed communications, semiconductor materials are required to have low dielectric constants, low dielectric loss tangents, and thin layers in order to reduce transmission loss. To achieve this, the addition of hollow resin particles made from acrylic or styrene to semiconductor materials is being considered.

[0003] For example, as conventional hollow resin particles, hollow resin particles obtained by suspension polymerization of a polymerizable monomer containing a crosslinkable hydrocarbon monomer such as divinylbenzene together with a hydrophobic solvent have been reported (Patent Documents 1 and 2). However, in recent years, the semiconductor component market has been studying miniaturization and high performance of electronic circuits, and when hollow resin particles are used for such applications, the hollow resin particles are required to be made smaller in size in order to miniaturize semiconductor components.

[0004] Furthermore, hollow polymer particles produced by seed polymerization have been reported as conventional hollow resin particles (Patent Document 3). However, seed polymerization tends to produce coarse particles due to poor swelling, making the hollow resin particles described in Patent Document 3 unsuitable for the above-mentioned applications. Furthermore, the hollow resin particles described in Patent Document 3 have a low ratio of crosslinkable monomers among the monomers polymerized into the particles, resulting in weak particle strength and the risk of crushing during processing. Furthermore, the inclusion of an acrylic composition results in a high dielectric loss tangent.

[0005] International Publication No. 2024-048093 International Publication No. 2023-074651 JP 2002-241448 A

[0006] When hollow resin particles are added to various semiconductor components, if the size of the hollow resin particles is not suitable for the size of the semiconductor component, it may cause irregularities in the base resin of the semiconductor component, which may lead to deterioration of the dielectric tangent and adhesion. Therefore, in order to thin semiconductor components, hollow resin particles with an average particle diameter of 1 μm or less and a reduced number of coarse particles are required. Therefore, the present invention has been made to solve the above problems, and its main object is to provide hollow resin particles with a small average particle diameter and a reduced number of coarse particles that can be applied to various components. It also aims to provide uses for such hollow resin particles.

[0007] [1] According to an embodiment of the present invention, hollow resin particles have a shell portion and a hollow portion surrounded by the shell portion, and have an average particle diameter of 0.1 μm to 1 μm. The hollow resin particles have a circularity of 0.97 or more and a proportion of coarse particles with a particle diameter of 5 μm or more is less than 5% by number. [2] In the hollow resin particles described in [1] above, the shell portion may contain a polymer (P) obtained by reaction of a monomer component (M) containing a crosslinkable monomer, and the content of the crosslinkable monomer in the monomer component (M) may be 20% to 100% by weight. [3] In the hollow resin particles described in [2] above, the monomer component (M) may contain a monofunctional monomer, and the content of the monofunctional monomer in the monomer component (M) may be 80% by weight or less. [4] In the hollow resin particles described in any one of [1] to [3] above, the hollow ratio may be 20% or more. [5] The hollow resin particles described in any one of [1] to [4] above may have a dielectric dissipation factor of less than 0.01 at a measurement frequency of 10 GHz. [6] The hollow resin particles described in [5] above may have a dielectric dissipation factor of 0.0030 or less. [7] The hollow resin particles described in any one of [1] to [6] above may have a relative dielectric constant of less than 2.0 at a measurement frequency of 10 GHz. [8] The hollow resin particles described in any one of [1] to [7] above may have a circularity of 0.80 or more and a proportion of coarse particles having a particle diameter of 5 μm or more of less than 5% by number. [9] The hollow resin particles described in any one of [1] to [8] above may be used in a resin composition for a semiconductor member.

[10] A dispersion according to an embodiment of the present invention contains hollow resin particles described in any one of [1] to [9] above.

[0008] According to an embodiment of the present invention, it is possible to provide hollow resin particles having a shell portion and a hollow portion surrounded by the shell portion, which have an average particle diameter of 1 μm or less and a reduced number of coarse particles that can be applied to various components, and also to provide uses of such hollow resin particles.

[0009] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to these embodiments.

[0010] 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)acryloyl" means "acryloyl and / or methacryloyl".

[0011] <<1. Hollow Resin Particles>> <<1-1. Structure and Properties of Hollow Resin Particles>> The hollow resin particles according to an embodiment of the present invention are hollow resin particles having a shell portion and a hollow portion surrounded by the shell portion, and have an average particle diameter of 0.1 μm to 1 μm. The hollow resin particles according to an embodiment of the present invention have a circularity of 0.97 or more, and the proportion of coarse particles having a particle diameter of 5 μm or more is less than 5% by number.

[0012] Here, "hollow" means that the interior is filled with a substance other than resin, such as a gas or liquid, and preferably means that the interior is filled with gas, as this can better demonstrate the effects of the present invention.

[0013] The hollow portion may consist of a single hollow region, or may consist of multiple hollow regions or a porous structure. In the hollow resin particles according to an embodiment of the present invention, the hollow portion preferably has a single hollow structure consisting of a single hollow region. When the hollow portion is a single hollow portion, the resin component constituting the shell portion is relatively large, and the shell portion may be less likely to collapse even when kneaded together with inorganic particles in a resin composition. Furthermore, when the hollow portion is a single hollow portion, penetration into the hollow portion of a substrate or the like can be effectively prevented.

[0014] By having an average particle diameter of 0.1 μm to 1 μm, the hollow resin particles can be used in resin compositions for a variety of applications. Hollow resin particles having such an average particle diameter are suitable, for example, for thinning semiconductor components. The average particle diameter of the hollow resin particles is preferably 0.1 μm to 0.9 μm, more preferably 0.15 μm to 0.8 μm, even more preferably 0.2 μm to 0.7 μm, and particularly preferably 0.3 μm to 0.6 μm. When the average particle diameter of the hollow resin particles is within the above range, the effects of the present invention can be more effectively achieved. If the average particle diameter of the hollow resin particles is less than 0.1 μm, the shell thickness will be relatively thin, which may result in hollow resin particles that do not have sufficient strength. If the average particle diameter of the hollow resin particles is greater than 1 μm, the applications of resin compositions in which the hollow resin particles can be used will be limited. Furthermore, if the average particle diameter of the hollow resin particles is greater than 1 μm, phase separation between the polymer and the solvent produced by polymerization of the monomer component during suspension polymerization may be difficult to occur, which may make it difficult to form the shell portion.

[0015] The hollow resin particles according to an embodiment of the present invention preferably have an average particle diameter of 100 nm to 900 nm, more preferably 200 nm to 800 nm, even more preferably 300 nm to 700 nm, and particularly preferably 400 nm to 600 nm. When the average particle diameter of the hollow resin particles according to an embodiment of the present invention is within the above range, the effects of the present invention can be more effectively exhibited.

[0016] Furthermore, in the hollow resin particles according to an embodiment of the present invention, the circularity is 0.97 or more, and the proportion of coarse particles having a particle diameter of 5 μm or more is less than 5% by number. The hollow resin particles according to an embodiment of the present invention, which have such a small number of coarse particles, enable the resin layer made from a resin composition containing the particles to be thin, making them suitable for semiconductor components and various other components. If the proportion of coarse particles is too large outside the above range, for example, when a resin layer is made from a resin composition containing the particles, it may be difficult to form a thin film or the thickness may vary. Furthermore, forming irregularities in the resin layer may lead to deterioration of the dielectric tangent and adhesion of the semiconductor component.

[0017] In hollow resin particles according to an embodiment of the present invention, the proportion of coarse particles having a circularity of 0.97 or more and a particle diameter of 5 μm or more is preferably 3% or less, more preferably 1% or less, even more preferably 0.5% or less, particularly preferably 0.1% or less, and most preferably 0%. Thus, hollow resin particles according to an embodiment of the present invention, which are substantially free of coarse particles having a particle diameter of 5 μm or more, can be used to reduce the dielectric constant and dielectric loss tangent of various components. In this specification, "hollow resin particles substantially free of coarse particles" means that the proportion of coarse particles having a circularity of 0.97 or more and a particle diameter of 5 μm or more is 0.5% or less.

[0018] In the hollow resin particles according to an embodiment of the present invention, the proportion of coarse particles having a circularity of 0.80 or more and a particle diameter of 5 μm or more is typically 5% or less, preferably 3% or less, more preferably 1% or less, even more preferably 0.5% or less, particularly preferably 0.1% or less, and most preferably 0%. Thus, the hollow resin particles according to an embodiment of the present invention, which are substantially free of coarse particles having a particle diameter of 5 μm or more, can be used to reduce the dielectric constant and the dielectric loss tangent of various components.

[0019] The proportion of coarse particles can be measured using, for example, a flow-type particle image analyzer, such as FPIA-3000S (manufactured by Sysmex Corporation) or Paasche Analyzer (manufactured by Hosokawa Micron Corporation).

[0020] The proportion of coarse particles can be measured, for example, as follows.

[0021] First, 0.05 g of sodium dodecylbenzenesulfonate was added as a dispersant to 20 mL of ion-exchanged water to obtain a surfactant aqueous solution. Next, 1.0 g of the polymerized slurry was added to the obtained surfactant aqueous solution, and ultrasonic waves were applied for 5 minutes using a BRANSON SONIFIER 450 ultrasonic disperser (output: 400 W, frequency: 20 kHz) manufactured by BRANSON to disperse the particles in the surfactant aqueous solution, thereby preparing a hollow resin particle dispersion for measurement.

[0022] When using an FPIA-3000S (manufactured by Sysmex Corporation) as the flow particle image analyzer, the obtained hollow resin particle dispersion is introduced into a flow particle image analyzer (FPIA-3000S, manufactured by Sysmex Corporation; equipped with a standard objective lens (10x magnification)) and measurement is performed. Particle Sheath (PSE-900A, manufactured by Sysmex Corporation) is used as the sheath liquid. Prior to measurement, the flow particle image analyzer is automatically focused using a suspension of standard polymer particles ("5200A" manufactured by Thermo Fisher Scientific Corporation, in which standard polystyrene particles are diluted with ion-exchanged water). The equivalent circle diameter (particle diameter) of each of 333,333 particles is measured within a particle circularity measurement range of 0.8 to 1.0, and this measurement is repeated three times. The percentage [%] of the number of particles having a measured particle diameter of 5 μm or more and a circularity of 0.97 or more relative to the total number of measured particles (1,000,000 particles) is defined as the "percentage of coarse particles having a circularity of 0.97 or more and a particle diameter of 5 μm or more," and the percentage [%] of the number of particles having a measured particle diameter of 5 μm or more and a circularity of 0.80 or more relative to the total number of measured particles (1,000,000 particles) is defined as the "percentage of coarse particles having a circularity of 0.80 or more and a particle diameter of 5 μm or more."

[0023] When a Paasche analyzer (manufactured by Hosokawa Micron Corporation) is used as the flow-type particle image analyzer for measurement, the hollow resin particle dispersion prepared as described above is introduced into a flow-type particle image analyzer (manufactured by Hosokawa Micron Corporation, Paasche analyzer; equipped with a standard objective lens (10x)) and measurement is performed. PAS sheath liquid (manufactured by Hosokawa Micron Corporation) is used as the sheath liquid. Other operations are the same as those for the FPIA-3000S method described above.

[0024] The hollow resin particles according to an embodiment of the present invention typically have a void ratio of 20% or more, preferably 25% to 80%, more preferably 30% to 75%, even more preferably 31% to 73%, particularly preferably 33% to 72%, and most preferably 36% to 71%. When the void ratio of the hollow resin particles is within the above range, better dielectric properties can be exhibited. In some cases, the hollow resin particles according to an embodiment of the present invention may have a void ratio of 60% or less, 55% or less, 50% or less, or even 45% or less.

[0025] The hollow resin particles according to an embodiment of the present invention preferably have a dielectric constant at a frequency of 10 GHz of less than 2.0, more preferably 1.9 or less, even more preferably 1.8 or less, and particularly preferably 1.7 or less. If the dielectric constant at a frequency of 10 GHz is within the above range, the hollow resin particles according to an embodiment of the present invention can exhibit excellent low dielectric properties. The lower limit of the dielectric constant at a frequency of 10 GHz of the hollow resin particles according to an embodiment of the present invention is, for example, 1.1.

[0026] The hollow resin particles according to an embodiment of the present invention preferably have a dielectric loss tangent at a frequency of 10 GHz of less than 0.010, more preferably 0.0070 or less, even more preferably 0.0060 or less, even more preferably 0.0055 or less, even more preferably 0.0050 or less, still more preferably 0.0045 or less, particularly preferably 0.0040 or less, and most preferably 0.0030 or less. If the dielectric loss tangent at a frequency of 10 GHz is within the above range, the hollow resin particles according to an embodiment of the present invention can exhibit excellent low dielectric properties. The lower limit of the dielectric loss tangent at a frequency of 10 GHz of the hollow resin particles according to an embodiment of the present invention is, for example, 0.0001.

[0027] The hollow resin particles according to an embodiment of the present invention typically have a residual metal content of 30 ppm or less. If the residual metal content of the hollow resin particles exceeds 30 ppm, there is a risk that excellent low dielectric properties may not be exhibited or uniform low dielectric properties may not be exhibited. Furthermore, if the residual metal content of the hollow resin particles exceeds 30 ppm, it may cause corrosion. The residual metal content of the hollow resin particles is preferably 20 ppm or less, more preferably 10 ppm or less, and even more preferably 5 ppm or less.

[0028] <1-2. Shell Portion> The shell portion preferably contains a polymer (P) obtained by reaction of a monomer component (M) containing a crosslinkable monomer.

[0029] The polymer (P) may be of one type only, or of two or more types.

[0030] The content of the polymer (P) in the shell portion is preferably 60% by weight to 100% by weight, more preferably 70% by weight to 100% by weight, even more preferably 80% by weight to 100% by weight, and particularly preferably 90% by weight to 100% by weight, in order to further exhibit the effects of the present invention.

[0031] The monomer component (M) preferably contains a crosslinkable monomer and a monofunctional monomer. Therefore, the polymer (P) is obtained, for example, by polymerizing the monomer component (M) containing the crosslinkable monomer and the monofunctional monomer, and preferably has a structural unit derived from the crosslinkable monomer and a structural unit derived from the monofunctional monomer.

[0032] The polymer (P) can be defined as being obtained by the reaction of the monomer component (M) in this way. This is because the polymer (P) becomes a polymer through the reaction of the monomer component (M), and therefore it is impossible and almost impractical to directly identify the polymer (P) by its structure ("impossible / impractical circumstances"). Therefore, the polymer (P) is appropriately defined as a "product" by the definition that it is "obtained by the reaction of the monomer component (M)."

[0033] The content of the crosslinkable monomer in the monomer component (M) is preferably 20% by weight to 100% by weight, more preferably 25% by weight to 98% by weight, even more preferably 28% by weight to 95% by weight, and particularly preferably 30% by weight to 90% by weight. When the shell portion contains the polymer (P) having such a structure, the effects of the present invention can be more effectively exhibited.

[0034] Examples of crosslinkable monomers include polyfunctional (meth)acrylic acid esters such as ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, and glycerin tri(meth)acrylate; polyfunctional acrylamide derivatives such as N,N'-methylenebis(meth)acrylamide and N,N'-ethylenebis(meth)acrylamide; polyfunctional allyl derivatives such as diallylamine and tetraallyloxyethane; and aromatic crosslinkable monomers such as divinylbenzene, divinylnaphthalene, diallyl phthalate, and divinylbiphenyl. In terms of being able to more effectively exhibit the effects of the present invention, aromatic crosslinkable monomers are preferred, and divinylbenzene is more preferred as the crosslinkable monomer. The crosslinkable monomer may be of one type, or two or more types.

[0035] The content of the aromatic crosslinkable monomer in the monomer component (M) is preferably 20% by weight or more, more preferably 25% by weight or more, even more preferably 28% by weight or more, even more preferably 30% by weight or more, even more preferably 35% by weight or more, particularly preferably 40% by weight or more, and most preferably 45% by weight or more, and is preferably less than 100% by weight, more preferably 99% by weight or less, even more preferably 98% by weight or less, particularly preferably 95% by weight or less, and most preferably 90% by weight or less, and in some cases may be 70% by weight or less. If the content of the aromatic crosslinkable monomer in the monomer component (M) is within the above range, the effects of the present invention can be more effectively exhibited. If the content of the aromatic crosslinkable monomer in the monomer component (M) is too low, the crosslink density will be low, which may reduce the strength of the shell portion.

[0036] Examples of monofunctional monomers include aromatic monofunctional monomers such as styrene, α-methylstyrene, ethylvinylbenzene, vinyltoluene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, vinylbiphenyl, and vinylnaphthalene; alkyl(meth)acrylate esters having 1 to 16 carbon atoms such as methyl(meth)acrylate, ethyl(meth)acrylate, butyl(meth)acrylate, and cetyl(meth)acrylate; and hydrophilic monofunctional monomers represented by the following formula (1). In terms of being able to further exhibit the effects of the present invention, the monofunctional monomer is preferably at least one selected from the group consisting of aromatic monofunctional monomers and hydrophilic monofunctional monomers. The monofunctional monomer preferably includes a hydrophilic monofunctional monomer.

[0037]

[0038] In general formula (1), R 1 represents H or CH3, R 2 represents an alkanediyl group having 1 to 10 carbon atoms or an alkenediyl group having 2 to 10 carbon atoms, R 3 represents a single bond, an alkanediyl group having 1 to 10 carbon atoms, an alkenediyl group having 2 to 10 carbon atoms, or a phenylene group; X represents a single bond, an ester bond, an ether bond, or a carbonyl group; n represents a number from 1 to 5; and n R 2 , X, R 3 are independent of each other.

[0039] The content of the monofunctional monomer in the monomer component (M) is preferably 80% by weight or less, more preferably 75% by weight or less, even more preferably 72% by weight or less, particularly preferably 70% by weight or less, and in some cases may be 30% by weight or less, 25% by weight or less, or even 20% by weight or less. The content of the monofunctional monomer in the monomer component (M) is preferably 1% by weight or more, more preferably 3% by weight or more.

[0040] The aromatic monofunctional monomer is preferably styrene or ethylvinylbenzene. The monofunctional monomer may be one kind or two or more kinds.

[0041] The content of the aromatic monofunctional monomer in the monomer component (M) is preferably 80% by weight or less, more preferably 75% by weight or less, even more preferably 72% by weight or less, and particularly preferably 70% by weight or less, and in some cases may be 30% by weight or less, 25% by weight or less, or even 20% by weight or less. The content of the aromatic monofunctional monomer in the monomer component (M) is preferably 1% by weight or more, more preferably 3% by weight or more. This results in a small average particle size and reduced coarse particles, making it possible to realize, for example, hollow resin particles that are substantially free of coarse particles.

[0042] In formula (1), R 2 represents an alkanediyl group having 1 to 10 carbon atoms or an alkenediyl group having 2 to 10 carbon atoms, and the alkanediyl group preferably has 2 to 6 carbon atoms, and more preferably has 2 to 4 carbon atoms. The alkanediyl group may be linear, branched, or cyclic. The alkenediyl group preferably has 2 to 6 carbon atoms, and more preferably has 2 to 4 carbon atoms. The alkenediyl group may be linear, branched, or cyclic.

[0043] R 2 With regard to R, examples of the alkanediyl group include a methylene group, an ethane-1,1-diyl group, an ethane-1,2-diyl group, a propane-1,2-diyl group, a propane-2,2-diyl group, a propane-1,3-diyl group, a 2-methylpropane-1,3-diyl group, a butane-1,3-diyl group, a butane-2,3-diyl group, and a butane-1,4-diyl group. 2 In this regard, examples of the alkenediyl group include an ethene-1,2-diyl group, a 1-propene-1,3-diyl group, a 2-butene-1,4-diyl group, a 1-methyl-1-butene-1,4-diyl group, and a 2-cyclohexene-1,4-diyl group.

[0044] In general formula (1), R 3represents a single bond, an alkanediyl group having 1 to 10 carbon atoms, an alkenediyl group having 2 to 10 carbon atoms, or a phenylene group. The alkanediyl group preferably has 2 to 6 carbon atoms, and more preferably has 2 to 4 carbon atoms. The alkanediyl group may be linear, branched, or cyclic. The alkenediyl group preferably has 2 to 6 carbon atoms, and more preferably has 2 to 4 carbon atoms. The alkenediyl group may be linear, branched, or cyclic.

[0045] R 3 With regard to R, examples of the alkanediyl group include those mentioned above. 3 With regard to the above, examples of the alkenediyl group include those mentioned above.

[0046] In general formula (1), X represents a single bond, an ester bond, an ether bond, or a carbonyl group. 2 -O-CO-R 3 or R 2 -CO-O-R 3 The structure may be:

[0047] Examples of the hydrophilic monofunctional monomer represented by general formula (1) include 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxyethyl maleic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl succinic acid, and 2-acryloyloxyethyl phthalic acid.

[0048] The hydrophilic monofunctional monomer represented by the general formula (1) may be a commercially available product, such as "Light Ester HO-MS (N)" manufactured by Kyoeisha Chemical Co., Ltd.

[0049] The content of the hydrophilic monofunctional monomer in the monomer component (M) is preferably 10% by weight or less, more preferably 8.0% by weight or less, even more preferably 5.0% by weight or less, even more preferably 3.0% by weight or less, particularly preferably 2.0% by weight or less, and most preferably 1.0% by weight or less, so as to more effectively exhibit the effects of the present invention. The content of the hydrophilic monofunctional monomer in the monomer component (M) is typically 0% by weight or more, preferably 0.1% by weight or more, more preferably 0.2% by weight or more, and even more preferably 0.5% by weight or more. When the content of the hydrophilic monofunctional monomer in the monomer component (M) is within the above range, the effects of the present invention can be more effectively exhibited.

[0050] The total content of the aromatic monofunctional monomer, aromatic crosslinkable monomer, and hydrophilic monofunctional monomer represented by general formula (1) in the monomer component (M) is preferably 80% by weight to 100% by weight, more preferably 85% by weight to 100% by weight, even more preferably 90% by weight to 100% by weight, and particularly preferably 95% by weight to 100% by weight, in terms of being able to further exhibit the effects of the present invention.

[0051] The monomer component (M) may contain any appropriate other monomer in addition to the crosslinkable monomer and the monofunctional monomer. The other monomer may be one type only, or two or more types.

[0052] The monomer component (M) may contain a compound (A) having an ether structure represented by formula (2) and a radical reactive group. The compound (A) reacts with the crosslinkable monomer or monofunctional monomer. When the monomer component (M) further contains the compound (A), the polymer (P) contains a structural unit derived from the ether structure represented by formula (2). By containing such a polymer (P), the resin particles according to an embodiment of the present invention can more effectively exhibit the effects of the present invention.

[0053]

[0054] As the compound (A), any appropriate compound may be used as long as it has the ether structure represented by the above formula (2) and a radical-reactive group, as long as it does not impair the effects of the present invention. In terms of further demonstrating the effects of the present invention, polyphenylene ether is a preferred example of such compound (A). Polyphenylene ether is a reactive polyphenylene ether that reacts with the above-mentioned crosslinkable monomer or monofunctional monomer in the presence of a polymerization initiator, and is typically a modified polyphenylene ether having a polymerizable double bond at at least one end. The modified polyphenylene ether preferably has polymerizable double bonds at both ends, and more preferably is a low-molecular-weight modified oligomer based on polyphenylene ether and having bifunctional groups. Here, "having bifunctional groups" means that functional groups having double bonds or functional groups having substituents having double bonds are located at both ends of the oligomer. In terms of more easily producing resin particles that are flexible and have excellent heat resistance, the number-average molecular weight Mn of the oligomer is preferably 500 to 3500.

[0055] A preferred example of such a modified polyphenylene ether is a compound represented by the following formula (3).

[0056]

[0057] In formula (3), n1 and n2 each independently represent an integer of 0 to 300, provided that at least one of them is an integer of 1 or more; L 3 represents a divalent linking group. 3is preferably selected from the group consisting of an alkylene group, an alkenylene group, -O-, -CO-, -CS-, -SO-, and -SO2-, more preferably an alkylene group, and even more preferably an isopropylidene group (-C(CH3)2-). Commercially available products of the compound represented by formula (3) include, for example, the "Noryl (registered trademark)" series (such as Noryl (registered trademark) SA9000) (manufactured by SABIC). As described above, the modified polyphenylene ether preferably has (meth)acryloyl groups at both ends. That is, compound (A) may be a polyphenylene ether having (meth)acryloyl groups at both ends.

[0058] Another preferred example of the modified polyphenylene ether is a compound represented by the following formula (4).

[0059]

[0060] In formula (4), n1 and n2 each independently represent an integer of 0 to 300, provided that at least one of them is an integer of 1 or greater. Commercially available products of the compound represented by formula (4) include, for example, the trade name "OPE-2St" series (manufactured by Mitsubishi Gas Chemical Company, Ltd.) and the trade name "DPPE-VBT50" (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).

[0061] Other commercially available polyphenylene ether products include, for example, the trade name "Iupiace (registered trademark)" series (manufactured by Mitsubishi Chemical Corporation) and the trade name "Zylon (registered trademark)" series (manufactured by Asahi Kasei Corporation).

[0062] The shell portion may contain any appropriate other component as long as the effects of the present invention are not impaired. For example, the shell portion may contain a non-crosslinkable polymer in addition to the polymer (P). The non-crosslinkable polymer may be one type or two or more types. The inclusion of a non-crosslinkable polymer can promote phase separation of polymerized oil droplets during suspension polymerization, making it easier to form uniform particles, and as a result, excellent low dielectric properties and uniform low dielectric properties can be exhibited.

[0063] Any suitable non-crosslinked polymer may be used as the non-crosslinked polymer as long as it does not impair the effects of the present invention. Such non-crosslinked polymers are preferably non-crosslinked polymers having a number-average molecular weight of 500 to 200,000, and examples thereof include at least one selected from the group consisting of paraffin, polyolefin, and styrene-based polymer. The shell portion may contain a hydrocarbon-based resin. When a non-crosslinked polymer having a number-average molecular weight of less than 500 is used, phase separation may be difficult to occur, which may make it difficult to form the shell portion. When a non-crosslinked polymer having a number-average molecular weight of more than 200,000 is used, the viscosity of the oil droplets increases, resulting in a larger average particle size. This may make it difficult to form the shell portion due to the increased viscosity of the oil droplets, which may make it difficult to form the phase separation between the polymer and the solvent produced by the polymerization of the monomer components during suspension polymerization.

[0064] The hydrocarbon-based resin may be of only one type, or may be of two or more types. When the shell portion contains a hydrocarbon-based resin, it becomes easier to construct a particle structure having a shell portion and a hollow portion surrounded by the shell portion. Furthermore, when the shell portion contains a hydrocarbon-based resin, the effects of the present invention can be more effectively achieved. The shell portion may contain 0 to 10 parts by weight of the hydrocarbon-based resin relative to 100 parts by weight of the total amount of the polymer (P) and the hydrocarbon-based resin. In order to further improve the effects of the present invention, the proportion of the hydrocarbon-based resin relative to 100 parts by weight of the total amount of the polymer (P) and the hydrocarbon-based resin is preferably 1 to 10 parts by weight, more preferably 1 to 8 parts by weight, even more preferably 2 to 8 parts by weight, particularly preferably 2 to 6 parts by weight, and most preferably 2 to 5 parts by weight. Alternatively, the hydrocarbon-based resin may be 1 to 5 parts by weight. When the proportion of the hydrocarbon-based resin is within the above range, the effects of the present invention can be more effectively achieved. This allows hollow resin particles to have a small average particle size and a reduced amount of coarse particles, for example, hollow resin particles that are substantially free of coarse particles, and hollow resin particles with excellent dielectric properties.

[0065] Any appropriate compound may be used as the hydrocarbon resin as long as it does not impair the effects of the present invention. Examples of hydrocarbon resins include aliphatic / aromatic hydrocarbon resins, aromatic hydrocarbon resins, alicyclic hydrocarbon resins, and aliphatic hydrocarbon resins. The hydrocarbon resin is preferably at least one selected from the group consisting of aliphatic / aromatic hydrocarbon resins, aromatic hydrocarbon resins, and aliphatic hydrocarbon resins, more preferably at least one selected from the group consisting of aliphatic / aromatic hydrocarbon resins and aromatic hydrocarbon resins, and even more preferably an aliphatic / aromatic hydrocarbon resin. Based on the above, hollow resin particles with a small average particle size and reduced coarse particles can be realized, for example, hollow resin particles substantially free of coarse particles, and thus hollow resin particles with excellent dielectric properties can be realized. As a result, when hollow resin particles are mixed with a resin such as a thermosetting resin to form a resin composition, the hollow resin particles are less likely to undergo substantial changes even when heated during molding or soldering of the thermosetting resin containing the hollow resin particles, thereby enabling the resin composition to better exhibit the dielectric properties expected of the resin composition. These hydrocarbon resins may be used alone or in combination of two or more.

[0066] The aliphatic / aromatic hydrocarbon resin refers to a hydrocarbon resin obtained by copolymerizing an aliphatic hydrocarbon and an aromatic hydrocarbon, such as a resin polymerized using styrene, vinyltoluene, indene, or piperylene as a main raw material.

[0067] The aromatic hydrocarbon resin is a resin obtained by polymerizing, for example, styrene, vinyltoluene, indene, or the like as a main raw material.

[0068] The alicyclic hydrocarbon resin is, for example, a resin obtained by hydrogenating an aliphatic / aromatic hydrocarbon resin or an aromatic hydrocarbon resin.

[0069] The aliphatic hydrocarbon resin is a hydrocarbon resin obtained by polymerizing one or more aliphatic hydrocarbons having a polymerizable unsaturated bond.

[0070] Examples of paraffin include paraffin wax and liquid paraffin.

[0071] Examples of polyolefins include polyethylene, polypropylene, and poly-α-olefins.

[0072] Examples of styrene-based polymers include polystyrene, styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, styrene-butadiene-styrene copolymer, etc. The styrene-based polymer may be a block copolymer or a styrene-butadiene-styrene block copolymer.

[0073] The shell portion may contain fully hydrogenated polybutadiene as the non-crosslinkable polymer.

[0074] The content of the non-crosslinkable polymer in the shell portion is preferably 0 to 40% by weight, more preferably 0 to 30% by weight, and even more preferably 1 to 20% by weight, in order to further exhibit the effects of the present invention. If the content of the non-crosslinkable polymer in the shell portion is too high, there is a risk that excellent low dielectric properties or uniform dielectric properties may not be exhibited.

[0075] <<Method for Producing Hollow Resin Particles>> The hollow resin particles according to an embodiment of the present invention can be produced by any appropriate method as long as the effects of the present invention are not impaired.

[0076] In a typical method for producing hollow resin particles according to an embodiment of the present invention, a monomer component (M) containing a crosslinkable monomer and an oil phase containing an organic solvent are dispersed in an aqueous phase containing an aqueous medium and a surfactant, followed by suspension polymerization. The monomer component (M) preferably contains a crosslinkable monomer and a monofunctional monomer, and more preferably contains an aromatic crosslinkable monomer and at least one selected from the group consisting of an aromatic monofunctional monomer and a hydrophilic monofunctional monomer.

[0077] For the monomer component (M), the explanation in the section "Shell Portion" above can be applied.

[0078] The organic solvent may be one type only, or two or more types may be used. Any appropriate organic solvent may be used as the organic solvent as long as the effects of the present invention are not impaired. As such an organic solvent, an organic solvent having a boiling point of less than 100°C is preferably used. By using an organic solvent having a boiling point of less than 100°C as the organic solvent, it becomes easy to remove the solvent from the hollow portions of the obtained hollow resin particles, and it becomes possible to reduce production costs.

[0079] Examples of organic solvents having a boiling point of less than 100° C. include heptane, hexane, cyclohexane, methyl acetate, ethyl acetate, methyl ethyl ketone, chloroform, and carbon tetrachloride.

[0080] The amount of the organic solvent used may be any appropriate amount as long as it does not impair the effects of the present invention, for example, 10 to 60 parts by weight per 100 parts by weight of the monomer component (M).

[0081] The oil phase preferably contains a polymerization initiator. The polymerization initiator may be one type or two or more types. Any appropriate polymerization initiator may be used as the polymerization initiator as long as it does not impair the effects of the present invention.

[0082] Examples of the polymerization initiator include organic peroxides such as cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, benzoyl peroxide, orthochlorobenzoyl peroxide, orthomethoxybenzoyl peroxide, lauroyl peroxide, 3,5,5-trimethylhexanoyl peroxide, dimethylbis(tert-butylperoxy)hexane, dimethylbis(tert-butylperoxy)hexyne-3, bis(tert-butylperoxyisopropyl)benzene, bis(tert-butylperoxy)trimethylcyclohexane, butyl-bis(tert-butylperoxy)valerate, 2-ethylhexaneperoxy acid tert-butyl, dibenzoyl peroxide, paramenthane hydroperoxide, and tert-butyl peroxybenzoate; 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(2,4-dimethylvaleronitrile), azo compounds such as 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).

[0083] The polymerization initiator may be a polymerization initiator having a 10-hour half-life temperature of 90° C. or less.

[0084] The amount of the polymerization initiator used may be any appropriate amount as long as it does not impair the effects of the present invention, for example, 0.1 to 5 parts by weight per 100 parts by weight of the monomer component (M).

[0085] The oil phase may contain a non-crosslinkable polymer. The non-crosslinkable polymer may be one type or two or more types. For the non-crosslinkable polymer, the explanation in the above section <1-2. Shell Portion> may be used.

[0086] In addition to the above-mentioned components, the oil phase may contain any other appropriate components as long as the effects of the present invention are not impaired. Such other components may be one type only, or two or more types.

[0087] Examples of aqueous media include water and mixed media of water and lower alcohols (alcohols having 5 or less carbon atoms, such as methanol, ethanol, and isopropyl alcohol). As the water, at least one selected from the group consisting of ion-exchanged water and distilled water is preferred.

[0088] The amount of the aqueous medium used may be any appropriate amount as long as the effects of the present invention are not impaired. Such an amount is preferably 100 to 2,000 parts by weight, and more preferably 200 to 1,000 parts by weight, relative to 100 parts by weight of the oil phase. By adjusting the amount of the aqueous medium used within the above range, the dispersion stability of the monomer during polymerization can be improved, and the generation of agglomerates of resin particles during polymerization can be suppressed.

[0089] The aqueous phase preferably contains a surfactant. Any appropriate surfactant may be used as the surfactant as long as it does not impair the effects of the present invention. The surfactant may be one type or two or more types. Examples of such surfactants include anionic surfactants, cationic surfactants, nonionic surfactants, and zwitterionic surfactants.

[0090] Examples of anionic surfactants include sodium oleate; fatty acid soaps such as castor oil potassium soap; polysulfonates; polycarboxylates; alkyl sulfate salts such as sodium lauryl sulfate and ammonium lauryl sulfate; alkylbenzene sulfonates such as sodium dodecylbenzene sulfonate; alkylaryl sulfonates; alkylnaphthalenesulfonates; alkanesulfonates; dialkyl sulfonates; dialkyl sulfosuccinates; alkyl phosphates; alkyl phosphoric acid ester salts; naphthalenesulfonate formalin condensates or salts thereof, such as the sodium salt of β-naphthalenesulfonate formalin condensate; polyoxyethylene alkylphenyl ether sulfate salts such as polyoxyethylene nonylphenyl ether sulfate salt; polyoxyethylene sulfonated phenyl ether phosphate; polyoxyethylene alkyl ether sulfates such as sodium polyoxyethylene lauryl ether sulfate and ammonium polyoxyethylene lauryl ether sulfate; polyoxyethylene alkyl sulfate salts; polyoxyethylene alkyl phosphoric acid sulfonates; glycerol borate fatty acid esters; polyoxyethylene glycerol fatty acid esters; phosphate surfactants; and phosphite surfactants. The anionic surfactant may be one type or two or more types. The counter cation of the anionic group is preferably an ammonium salt. By using such a surfactant, the amount of metal residue can be reduced.

[0091] Examples of cationic surfactants include alkylamine salts such as laurylamine acetate and stearylamine acetate, and quaternary ammonium salts such as lauryltrimethylammonium chloride. Only one type of cationic surfactant may be used, or two or more types may be used.

[0092] Examples of nonionic surfactants include (meth)acrylate sulfate ester surfactants (commercially available products include RMA-564, RMA-568, and RMA-1114 manufactured by Nippon Nyukazai Co., Ltd.); polyoxyalkylene branched decyl ethers; polyoxyalkylene alkyl ethers such as polyoxyethylene tridecyl ether, polyoxyethylene isodecyl ether, polyoxyethylene lauryl ether, and polyoxyethylene oleyl cetyl ether; polyoxyalkylene aryl ethers such as polyoxyethylene naphthyl ether and polyoxyethylene phenyl ether; polyoxyalkylene alkylaryl ethers; polyether polyols; polyoxyethylene styrenated phenyl ether; polyoxyethylene polyoxypropylene glycol; polyoxyethylene glyceryl isostearate; polyoxyethylene fatty acid esters; sorbitan fatty acid esters; polyoxysorbitan fatty acid esters; polyoxyethylene alkylamines; glycerin fatty acid esters; and oxyethylene-oxypropylene block polymers. The nonionic surfactants may be used alone or in combination of two or more types.

[0093] Examples of the zwitterionic surfactant include lauryl dimethylamine oxide, alkyldiaminoethylglycine hydrochloride, sodium laurylaminopropionate, alkylbetaine, etc. Only one type of zwitterionic surfactant may be used, or two or more types may be used.

[0094] A reactive surfactant having a vinyl group may be used as the surfactant. The reactive surfactant having a vinyl group may be one type only, or two or more types may be used. When a reactive surfactant having a vinyl group is used, the reactive surfactant having a vinyl group can be incorporated into the polymer (P), so that the surfactant can be effectively unevenly distributed on the particle surface in suspension polymerization, and the surfactant effect can be improved. As a result, an excellent surfactant effect can be obtained, particle aggregation and coalescence can be suppressed during production, the by-production of non-standard particles can be reduced, and more uniform low dielectric properties can be exhibited.

[0095] Examples of reactive surfactants having a vinyl group include anionic surfactants having a vinyl group and nonionic surfactants having a vinyl group.

[0096] Examples of anionic surfactants having a vinyl group include polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ester ammonium, polyoxyethylene styrenated propenyl phenyl ether sulfate ester ammonium, polyoxyalkylene alkenyl ether sulfate, α-sulfo-ω-(1-alkoxymethyl-2-(2-propenyloxy)ethoxy)-poly(oxy-1,2-ethanediyl)ammonium, polyoxypropylene allyl ether phosphate, and bis(polyoxyethylene phenyl ether) methacrylate sulfate. Furthermore, the counter cation of the anionic group is preferably an ammonium salt. By using such surfactants, the average particle size of the hollow resin particles can be further reduced, and the amount of coarse particles can be reduced. Furthermore, the amount of metal residue can be reduced.

[0097] Commercially available polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ester ammonium products include, for example, trade name "Aqualon KH-10" and trade name "Aqualon KH-1025" (a 25 wt % aqueous solution of "Aqualon KH-10") manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.

[0098] Commercially available polyoxyethylene styrenated propenyl phenyl ether ammonium sulfate esters include, for example, trade names "AQUALON AR-10," "AQUALON AR-20," "AQUALON AR-3025" (a 25 wt % aqueous solution of "AQUALON AR-30"), and "AQUALON AR-1025" (a 25 wt % aqueous solution of "AQUALON AR-10") manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.

[0099] An example of a commercially available polyoxyalkylene alkenyl ether ammonium sulfate is "Latemul PD-104" manufactured by Kao Corporation.

[0100] Commercially available α-sulfo-ω-(1-alkoxymethyl-2-(2-propenyloxy)ethoxy)-poly(oxy-1,2-ethanediyl)ammonium products include, for example, trade names "ADEKA REASOAP SR-10" and "ADEKA REASOAP SR-20" manufactured by ADEKA Corporation.

[0101] An example of a commercially available polyoxypropylene allyl ether phosphate ester is "ADEKA REASOAP PP-70" manufactured by ADEKA Corporation.

[0102] An example of a commercially available product of bis(polyoxyethylene phenyl ether) methacrylate sulfate is "Antox MS-60" manufactured by Nippon Nyukazai Co., Ltd.

[0103] Examples of nonionic surfactants having a vinyl group include polyoxyethylene styrenated propenyl phenyl ether, polyoxyethylene-1-(allyloxymethyl) alkyl ether, and polyoxyalkylene alkenyl ether.

[0104] Commercially available polyoxyethylene styrenated propenyl phenyl ethers include, for example, trade names "Aqualon AN-10," "Aqualon AN-20," "Aqualon AN-30," and "Aqualon AN-5065" manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.

[0105] Examples of commercially available polyoxyethylene-1-(allyloxymethyl) alkyl ethers include products manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd. under the trade names "Aqualon KN-10," "Aqualon KN-20," "Aqualon KN-30," and "Aqualon KN-5065," and products manufactured by ADEKA Corporation under the trade names "ADEKA REASOAP ER-10," "ADEKA REASOAP ER-20," "ADEKA REASOAP ER-30," and "ADEKA REASOAP ER-40."

[0106] Commercially available polyoxyalkylene alkenyl ethers include, for example, those available under the trade names "Latemul PD-420," "Latemul PD-430," and "Latemul PD-450" manufactured by Kao Corporation.

[0107] The surfactant may be used in any appropriate amount as long as the effects of the present invention are not impaired, and the amount used is preferably 0.001 to 5 parts by weight, more preferably 0.005 to 3 parts by weight, and even more preferably 0.01 to 1 part by weight, relative to 100 parts by weight of the oil phase.

[0108] In addition to the above-mentioned components, the aqueous phase may contain any other appropriate components as long as the effects of the present invention are not impaired.

[0109] As a method for mixing the oil phase and the aqueous phase, any appropriate method can be adopted as long as it can carry out suspension polymerization and does not impair the effects of the present invention.

[0110] The suspension is prepared by mixing and stirring the oil phase and the aqueous phase. Typically, this is done by dispersing the oil phase in the aqueous phase. Any appropriate dispersion method can be used to disperse the oil phase in the aqueous phase, as long as it allows the oil phase to exist in droplet form in the aqueous phase, as long as it does not impair the effects of the present invention. A typical dispersion method is a dispersion method using a homogenizer, such as an ultrasonic homogenizer or a high-pressure homogenizer.

[0111] Any appropriate method can be adopted as the suspension polymerization method as long as it does not impair the effects of the present invention.

[0112] The polymerization temperature may be any suitable temperature suitable for suspension polymerization within a range that does not impair the effects of the present invention, such as 30°C to 95°C.

[0113] The polymerization time may be any suitable time suitable for suspension polymerization as long as it does not impair the effects of the present invention. Such a polymerization time is preferably 1 hour to 20 hours.

[0114] Post-heating, which is preferably carried out after polymerization, is a treatment suitable for obtaining hollow resin particles with a high degree of perfection.

[0115] The temperature for post-heating preferably carried out after polymerization can be any appropriate temperature within a range that does not impair the effects of the present invention. The temperature for such post-heating is preferably 50°C to 120°C.

[0116] The time for post-heating preferably carried out after polymerization can be any appropriate time within the range that does not impair the effects of the present invention, and the time for such post-heating is preferably 1 hour to 10 hours.

[0117] The above polymerization produces a slurry, which is a dispersion containing microcapsule particles encapsulating the organic solvent used in the oil phase. The slurry obtained by suspension polymerization can be subjected to distillation, solvent removal, washing, drying, classification, etc., as necessary, to produce hollow resin particles.

[0118] Dispersion The hollow resin particles according to an embodiment of the present invention may be used as a dispersion, if necessary. Such a dispersion contains the hollow resin particles according to an embodiment of the present invention and a dispersion medium, and the hollow resin particles according to an embodiment of the present invention are dispersed in the dispersion medium as a dispersoid. For example, the dispersion of microcapsule particles encapsulating an organic solvent obtained after the polymerization step in the above-described production method may be used as is, or may be used as a solvent dispersion in which the dispersion medium has been replaced with another dispersion medium.

[0119] <<Uses of Hollow Resin Particles>> The hollow resin particles according to an embodiment of the present invention can be used in a variety of applications. Because the effects of the present invention can be more effectively utilized, the hollow resin particles according to an embodiment of the present invention are suitable for semiconductor components, and can be typically used in resin compositions for semiconductor components. Furthermore, in addition to the use in the resin compositions for semiconductor components described above, the hollow resin particles according to an embodiment of the present invention can also be used in applications in which the effects of the present invention can be utilized, such as paint compositions, heat-insulating resin compositions, light-diffusing resin compositions, and light-diffusing films.

[0120] <<Resin composition for semiconductor member>> The hollow resin particles according to an embodiment of the present invention have a small particle size and a reduced amount of coarse particles. Therefore, for example, the hollow resin particles can be suitably used in a resin composition for a semiconductor member in that they can impart low dielectric properties to a thin-layered semiconductor member.

[0121] The resin composition for a semiconductor member according to an embodiment of the present invention includes hollow resin particles according to an embodiment of the present invention. Such a resin composition for a semiconductor member is suitable for use as an encapsulant for a semiconductor chip, for example.

[0122] The term "semiconductor member" refers to a member that constitutes a semiconductor, such as a semiconductor package or a semiconductor module. In this specification, the term "resin composition for a semiconductor member" refers to a resin composition used for a semiconductor member.

[0123] A semiconductor package is constructed using an IC chip as an essential component and at least one member selected from a mold resin, an underfill material, a mold underfill material, a die bond material, a prepreg for a semiconductor package substrate, a metal-clad laminate for a semiconductor package substrate, and a build-up material for a printed circuit board for a semiconductor package.

[0124] A semiconductor module is constructed using a semiconductor package as an essential component and at least one member selected from a prepreg for a printed circuit board, a metal-clad laminate for a printed circuit board, a build-up material for a printed circuit board, a solder resist material, a coverlay film, an electromagnetic wave shielding film, and an adhesive sheet for a printed circuit board.

[0125] <<Coating Composition>> The hollow resin particles according to an embodiment of the present invention can impart an excellent appearance to a coating film containing the hollow resin particles, and therefore can be suitably used in a coating composition.

[0126] Such coating compositions include hollow resin particles according to embodiments of the present invention.

[0127] The coating composition preferably contains at least one selected from a binder resin and a UV-curable resin. The binder resin may be one type or two or more types. The UV-curable resin may be one type or two or more types.

[0128] Any suitable binder resin can be used as long as it does not impair the effects of the present invention. Examples of such binder resins include resins soluble in organic solvents or water, and emulsion-type aqueous resins that can be dispersed in water. Specific examples of binder resins include acrylic resins, alkyd resins, polyester resins, polyurethane resins, chlorinated polyolefin resins, and amorphous polyolefin resins.

[0129] As the UV-curable resin, any appropriate UV-curable resin can be used as long as it does not impair the effects of the present invention. Examples of such UV-curable resins include polyfunctional (meth)acrylate resins and polyfunctional urethane acrylate resins. Polyfunctional (meth)acrylate resins are preferred, and polyfunctional (meth)acrylate resins having three or more (meth)acryloyl groups in one molecule are more preferred. Specific examples of polyfunctional (meth)acrylate resins having three or more (meth)acryloyl groups in one molecule include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, 1,2,4-cyclohexane tetra(meth)acrylate, pentaglycerol triacrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol triacrylate, and tripentaerythritol hexaacrylate.

[0130] When the coating composition contains at least one selected from a binder resin and a UV-curable resin, any appropriate content ratio can be adopted depending on the purpose. Typically, the hollow resin particles according to the embodiment of the present invention are preferably contained in an amount of 5 to 50% by weight, more preferably 10 to 50% by weight, and even more preferably 20 to 40% by weight, based on the total amount of the binder resin (in terms of solids content in the case of an emulsion-type aqueous resin), the at least one selected from the UV-curable resin, and the hollow resin particles according to the embodiment of the present invention.

[0131] When a UV-curable resin is used, a photopolymerization initiator is preferably used in combination. Any appropriate photopolymerization initiator can be used as long as it does not impair the effects of the present invention. Examples of such photopolymerization initiators include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, α-hydroxyalkylphenones, α-aminoalkylphenones, anthraquinones, thioxanthones, azo compounds, peroxides (described in JP 2001-139663 A, etc.), 2,3-dialkyldione compounds, disulfide compounds, fluoroamine compounds, aromatic sulfonium compounds, onium salts, borate salts, active halogen compounds, and α-acyloxime esters.

[0132] The coating composition may contain a solvent. The solvent may be one type only, or two or more types. When the coating composition according to the embodiment of the present invention contains a solvent, any appropriate content ratio may be adopted depending on the purpose.

[0133] As the solvent, any appropriate solvent can be used as long as it does not impair the effects of the present invention. Such a solvent is preferably a solvent that can dissolve or disperse a binder resin or a UV-curable resin. Examples of such solvents include, for oil-based paints, hydrocarbon solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; ester solvents such as ethyl acetate and butyl acetate; and ether solvents such as dioxane, ethylene glycol diethyl ether, and ethylene glycol monobutyl ether. For water-based paints, examples of such solvents include water and alcohols.

[0134] The coating composition may be diluted to adjust the viscosity as needed. Any appropriate diluent may be used depending on the purpose. Examples of such diluents include the solvents mentioned above. The diluent may be one type or two or more types.

[0135] The coating composition may contain other components, as needed, such as a coating surface conditioner, a flowability conditioner, an ultraviolet absorber, a light stabilizer, a curing catalyst, an extender pigment, a coloring pigment, a metallic pigment, a mica powder pigment, or a dye.

[0136] When forming a coating film using a coating composition, any appropriate coating method can be adopted depending on the purpose, such as spray coating, roll coating, brush coating, reverse roll coating, gravure coating, die coating, comma coating, and spray coating.

[0137] When forming a coating film using a coating composition, any suitable formation method can be adopted depending on the purpose. Such a formation method includes, for example, applying the composition to any coating surface of a substrate to form a coating film, drying the coating film, and then curing the coating film as needed to form a coating film. Examples of substrates include metal, wood, glass, and plastics (PET (polyethylene terephthalate), PC (polycarbonate), acrylic resin, TAC (triacetyl cellulose), etc.).

[0138] The hollow resin particles according to an embodiment of the present invention can impart excellent heat insulating properties to a coating film containing the hollow resin particles, and therefore can be suitably used in a heat insulating resin composition. A coating film containing the hollow resin particles according to an embodiment of the present invention can exhibit excellent reflectance in the wavelength range from ultraviolet light to near-infrared light.

[0139] Such a heat insulating resin composition contains hollow resin particles according to an embodiment of the present invention.

[0140] The heat insulating resin composition preferably contains at least one selected from a binder resin and a UV curable resin. The above-mentioned explanation of the coating composition can be applied to the binder resin and the UV curable resin.

[0141] The heat insulating resin composition may contain a solvent. Regarding the solvent, the above explanation regarding the coating composition may be applied.

[0142] The heat insulating resin composition may be diluted to adjust the viscosity as needed. The above-mentioned explanation of the coating composition can be applied to the diluent.

[0143] The heat insulating resin composition may contain other components, as needed, such as a coating surface conditioner, a flowability conditioner, an ultraviolet absorber, a light stabilizer, a curing catalyst, an extender pigment, a color pigment, a metal pigment, a mica powder pigment, or a dye.

[0144] When a coating film is formed using the heat insulating resin composition, the coating method and forming method can be applied as described above for the coating composition.

[0145] <Light-diffusing resin composition> The hollow resin particles according to an embodiment of the present invention can impart excellent light-diffusing properties to a coating film containing the hollow resin particles, and therefore can be suitably used in a light-diffusing resin composition.

[0146] Such a light-diffusing resin composition contains hollow resin particles according to an embodiment of the present invention.

[0147] The diffusing resin composition preferably contains at least one selected from a binder resin and a UV-curable resin. The binder resin and the UV-curable resin may be the same as those described above for the coating composition.

[0148] The light-diffusing resin composition may contain a solvent. The above-mentioned explanation of the coating composition may be applied to the solvent.

[0149] The light-diffusing resin composition may be diluted to adjust the viscosity as needed. The above-mentioned explanation of the coating composition can be applied to the diluent.

[0150] The light-diffusing resin composition may contain other components, such as a coating surface conditioner, a flowability conditioner, an ultraviolet absorber, a light stabilizer, a curing catalyst, an extender pigment, a color pigment, a metal pigment, a mica powder pigment, or a dye, as needed.

[0151] When a coating film is formed using the light-diffusing resin composition, the coating method and formation method can be the same as those described above for the coating composition.

[0152] <Light Diffusion Film> The hollow resin particles according to an embodiment of the present invention can impart excellent light diffusibility to a film having a coating film containing the hollow resin particles, and can therefore be suitably used in a light diffusing film.

[0153] Such a light-diffusing film includes hollow resin particles according to an embodiment of the present invention.

[0154] The light diffusion film includes a light diffusion layer formed from the light-diffusing resin composition described above and a substrate. The light diffusion layer may or may not be the outermost layer of the light diffusion film. The light diffusion film according to an embodiment of the present invention may include any appropriate other layer depending on the purpose. Examples of such other layers include a protective layer, a hard coat layer, a planarizing layer, a high refractive index layer, an insulating layer, a conductive resin layer, a conductive metal fine particle layer, a conductive metal oxide fine particle layer, and a primer layer.

[0155] Examples of the substrate include metal, wood, glass, plastic film, plastic sheet, plastic lens, plastic panel, cathode ray tube, fluorescent display tube, and liquid crystal display panel. Examples of the plastic that constitutes the plastic film, plastic sheet, plastic lens, and plastic panel include polyethylene terephthalate (PET), polycarbonate (PC), acrylic resin, and triacetyl cellulose (TAC).

[0156] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0157] <Average Particle Diameter> The Z-average particle diameter of hollow resin particles was measured using dynamic light scattering, and the measured Z-average particle diameter was used as the average particle diameter of the obtained hollow resin particles. Specifically, the obtained hollow resin particles or particles were first diluted with ion-exchange water to a concentration of 0.1 wt %. The aqueous dispersion was then irradiated with laser light, and the scattered light intensity from the hollow resin particles was measured over time in microseconds. The detected scattering intensity distribution due to the hollow resin particles was then fitted to a normal distribution, and the Z-average particle diameter of the hollow resin particles or particles was calculated using cumulant analysis. This Z-average particle diameter measurement can be easily performed using a commercially available particle size measurement device. In the following examples and comparative examples, the Z-average particle diameter was measured using a particle size measurement device (Malvern Zetasizer Nano ZS). Typically, commercially available particle size measurement devices are equipped with data analysis software, which automatically analyzes the measurement data to calculate the Z-average particle diameter.

[0158] <Hollowness> The hollowness of hollow resin particles was obtained from the apparent density of the hollow resin particles. The apparent density of the hollow resin particles was measured using a vibration densitometer (trade name "DMA1001" manufactured by Anton Paar). Specifically, the hollow resin particles and a dispersion medium (trade name "ARUFON UP-1020" manufactured by Toa Gosei Co., Ltd., density 1.027 g / cm) were mixed together so that the proportion of hollow resin particles was 2% by weight. 3(25°C)) was defoamed and stirred using a defoaming mixer (manufactured by Thinky Corporation, product name "Awatori Rentaro ARE-100") to prepare a mixture for evaluation. The mixture for evaluation was filled into the measurement cell of a vibration-type density meter, and the vibration frequency of the mixture in the measurement cell was measured, thereby calculating the density of the mixture from the following formula (5). The apparent density of the air-encapsulated hollow resin particles was calculated from the densities of the mixture and the dispersion medium and their respective weight proportions in the mixture using the following formula (6). In equation (5), f is the frequency [Hz], M is the weight of the measurement cell [g], and V is the volume of the measurement cell [cm 3 ], ρ is the sample density [g / cm 3 ], and c represents the spring constant [N / mm]. In formula (6), ρ p is the apparent density of the hollow resin particles [g / cm 3 ], ρ d is the density of the dispersion medium [g / cm 3 ], x p is the weight ratio of hollow resin particles in the sample, x d represents the weight ratio of the dispersion medium in the sample. The hollow ratio of the hollow resin particles was calculated from the apparent density and the density of the shell using the following formula: Hollow ratio [%] = 100 - (100 × apparent density [g / cm 3 ]) / shell density [g / cm 3 ]

[0159] <Observation of the Presence and Shape of Hollow Portions> Hollow resin particles in the form of dry powder were surface treated (10 Pa, 5 mA, 10 seconds) using an "Osmium Coater Neoc-Pro" coating device manufactured by Meiwa Forsys. The hollow resin particles were then observed with a TEM (transmission electron microscope, H-7600 manufactured by Hitachi High-Technologies Corporation) to confirm the presence or absence of hollow portions and the shape of the hollow resin particles. Images were taken at an acceleration voltage of 80 kV and a magnification of 5,000x or 10,000x.

[0160] <Metal Residue Amount Measurement> The amount of metal residue was measured as follows. (Measurement Sample) 0.5 g of hollow resin particles was precisely weighed into a cleaned 50 mL plastic container. 1 mL of cleaning ethanol was added, and the mixture was thoroughly mixed and dispersed. 50 mL of ion-exchanged water was then added and thoroughly mixed. Ultrasonic cleaning and extraction was performed for approximately 10 minutes, and the mixture was then left to stand in a 60°C thermostatic chamber for 60 minutes. The slurry after standing was filtered through an aqueous 0.20 μm chromatographic disc, which was used as the measurement sample. (Measurement Method) The amount of metal residue in the measurement sample was measured under the following conditions. The amount of metal residue was determined from a previously prepared calibration curve. The amount of metal residue was calculated using the following formula: Metal Residue Amount (ppm) = Measured Metal Element Concentration (μg / mL) × 51 (mL) ÷ Sample Amount (g) The lower limit of quantitation was 1 ppm, and if the measurement result was below this lower limit of quantitation, the lower limit of quantitation of 1 ppm was used as the measurement result. (ICP measurement conditions) Measurement device = Shimadzu Corporation's "ICPE-9000" multi-type ICP optical emission spectrometer Measurement elements = Ca, K, Li, Mg, Na 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 elements mixed (base 5% HNO3): approximately 10 mg / L each, "XSTC-8" general-purpose mixed standard solution 13 elements mixed (base HO / trace HF): approximately 10 mg / L each

[0161] <Dielectric Properties of Hollow Resin Particles> The dielectric properties of the hollow resin particles were measured using a dielectric constant measurement device (ADMS01Nc series) manufactured by AET Corporation. The measurement was performed at a frequency of 10 GHz under the conditions of 23°C and a relative humidity of 51±1%. The relative dielectric constant and dielectric loss tangent of the hollow resin particles were calculated based on perturbation theory using a resonator.

[0162] <Proportion of Coarse Particles> The proportion of coarse particles was measured using a flow particle image analyzer (Sysmex Corporation's "FPIA (registered trademark)-3000S"). Alternatively, any Paasche analyzer (Hosokawa Micron Corporation) may be used. The specific measurement procedure is as follows. First, 0.05 g of sodium dodecylbenzenesulfonate was added as a dispersant to 20 mL of ion-exchanged water to obtain a surfactant aqueous solution. Next, 1.0 g of the polymerized slurry was added to the obtained surfactant aqueous solution, and ultrasonic waves were irradiated for 5 minutes using a BRANSON SONIFIER 450 ultrasonic disperser (output 400 W, frequency 20 kHz) manufactured by BRANSON Corporation to perform a dispersion treatment to disperse the particles in the surfactant aqueous solution, thereby preparing a dispersion for measurement. For the measurement, the above-mentioned flow particle image analyzer (Sysmex Corporation's "FPIA (registered trademark)-3000S") equipped with a standard objective lens (10x magnification) was used. The sheath liquid used in the flow particle image analyzer was a particle sheath ("PSE-900A" manufactured by Sysmex Corporation). The measurement dispersion prepared according to the above procedure was introduced into the flow particle image analyzer, and the equivalent circle diameter (particle diameter) of each of 333,333 particles was measured within the particle circularity measurement range of 0.8 to 1.0, and this was repeated three times. Prior to the start of the measurement, the flow particle image analyzer was automatically focused using a suspension of standard polymer particles ("5200A" manufactured by Thermo Fisher Scientific, Inc., prepared by diluting standard polystyrene particles with ion-exchange water). The percentage [%] of the number of particles having a measured particle diameter of 5 μm or more and a circularity of 0.97 or more relative to the total number of measured particles (1,000,000 particles) was defined as the "percentage of coarse particles having a circularity of 0.97 or more and a particle diameter of 5 μm or more," and the percentage [%] of the number of particles having a measured particle diameter of 5 μm or more and a circularity of 0.80 or more relative to the total number of measured particles (1,000,000 particles) was defined as the "percentage of coarse particles having a circularity of 0.80 or more and a particle diameter of 5 μm or more."

[0163] <Raw materials used> The raw materials used are as follows.

[0164] [Aromatic monofunctional monomers] Styrene

[0165] [Aromatic crosslinkable monomers] Divinylbenzene (DVB) 810 (manufactured by Nippon Steel Chemical & Material Co., Ltd., 81% by weight content, 19% by weight of which is ethylvinylbenzene (EVB)) (Examples 1 to 5, Examples 7 to 11, Comparative Example 1) Divinylbenzene (DVB) 960 (manufactured by Nippon Steel Chemical & Material Co., Ltd., 96% by weight content, 4% by weight of which is ethylvinylbenzene (EVB)) (Example 6)

[0166] [Hydrophilic monofunctional monomers] 2-methacryloyloxyethyl succinate (manufactured by Kyoeisha Chemical Co., Ltd., trade name "Light Ester HO-MS(N)") KAYAMER (registered trademark) PM-21 (manufactured by Nippon Kayaku Co., Ltd.)

[0167] [Other Monomers] Reactive low molecular weight polyphenylene ether (manufactured by SABIC, product name "Noryl (registered trademark) SA9000-111 resin")

[0168] [Reactive surfactants having a vinyl group] Polyoxyethylene styrenated propenyl phenyl ether sulfate ester ammonium salt (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "Aqualon AR-10") Bis(polyoxyethylene phenyl ether) methacrylate sulfate ester ammonium salt (manufactured by Nippon Nyukazai Co., Ltd., trade name "Antox MS-60") Polyoxyethylene styrenated propenyl phenyl ether (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name "Aqualon AN-5065")

[0169] [Non-crosslinkable polymers] Paraffin wax (Nucera Solutions, trade name "VYBAR260", number average molecular weight 2,600 to 4,000) Aliphatic / aromatic hydrocarbon resin (Tosoh, trade name "Petrotack 90", number average molecular weight 900) Fully hydrogenated polybutadiene (Nippon Soda, trade name "BI-3000", number average molecular weight 3,300) Styrene-butadiene-styrene block polymer (Nippon Soda, trade name "1,2-SBS-P35", number average molecular weight 35,000)

[0170] [Organic solvent] Heptane

[0171] [Polymerization initiator] Lauroyl peroxide (manufactured by NOF Corporation, trade name "Perloyl L")

[0172] [Aqueous medium] Ion-exchanged water 2% magnesium pyrophosphate dispersion

[0173] Example 1 After preparing the oil and aqueous phases according to the compositions shown in Table 1, the oil and aqueous phases were mixed and dispersed using a Polytron homogenizer "PT10-35" (manufactured by Central Scientific Trading Co., Ltd.) at a rotation speed of 7,000 rpm for 5 minutes. The mixture was then emulsified using a high-pressure emulsifier NVL-AS200 (manufactured by Yoshida Kikai Kogyo Co., Ltd.) at a processing pressure of 20 MPa to produce a suspension. The resulting suspension was heated at 70°C for 5 hours, then heated to 90°C and heated for 2 hours to carry out polymerization. The organic solvent was removed from the slurry obtained by polymerization by distillation, and large particles were then classified and removed using a 500-mesh (25 μm opening) wire mesh to obtain a slurry containing hollow resin particles. The resulting slurry was heated and dried to obtain hollow resin particles (1) as a dry powder. TEM analysis confirmed that the hollow resin particles (1) were hollow particles with a monohollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (1) was below the lower limit of quantitation.

[0174] [Example 2] Hollow resin particles (2) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (2) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (2) was below the lower limit of quantitation.

[0175] [Example 3] Hollow resin particles (3) were obtained in the same manner as in Example 1, except that the composition of the oil phase was changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (3) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (3) was below the lower limit of quantitation.

[0176] [Example 4] Hollow resin particles (4) were obtained in the same manner as in Example 1, except that the composition of the oil phase was changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (4) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (4) was below the lower limit of quantitation.

[0177] [Example 5] Hollow resin particles (5) were obtained in the same manner as in Example 1, except that the composition of the oil phase was changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (5) were hollow particles with a single hollow structure. The results are shown in Table 1.

[0178] [Example 6] Hollow resin particles (6) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (6) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (6) was below the lower limit of quantitation.

[0179] [Example 7] Hollow resin particles (7) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (7) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (7) was below the lower limit of quantitation.

[0180] [Example 8] Hollow resin particles (8) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (8) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (8) was below the lower limit of quantitation.

[0181] [Example 9] Hollow resin particles (9) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (9) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (9) was below the lower limit of quantitation.

[0182] [Example 10] Hollow resin particles (10) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (10) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (10) was below the lower limit of quantitation.

[0183] [Example 11] Hollow resin particles (11) were obtained in the same manner as in Example 1, except that the compositions of the oil phase and the water phase were changed as shown in Table 1. TEM measurement confirmed that the hollow resin particles (11) were hollow particles with a single hollow structure. The results are shown in Table 1. The amount of metal residue in the hollow resin particles (11) was below the lower limit of quantitation.

[0184] Comparative Example 1 A slurry containing hollow resin particles was obtained by the same polymerization method as in Example 1, except that the compositions of the oil phase and the aqueous phase were changed as shown in Table 1. Hydrochloric acid was added to the obtained slurry to decompose the magnesium pyrophosphate, and the solid content was separated by dehydration through filtration and purified by repeated washing with water. The solid was then dried by heating to obtain hollow resin particles (C1) as a dry powder. The results are shown in Table 1.

[0185]

[0186] <Performance Evaluation: Evaluation of Relative Dielectric Constant and Dielectric Loss Tangent of Particle-Added Film> 0.425 g of the particles (2) obtained in Example 2, 8.3 g of ethyl acetate, and 1.7 g of solvent-soluble polyimide KPI-MX300F (manufactured by Kawamura Sangyo Co., Ltd.) were degassed and stirred using a planetary stirring defoamer (manufactured by KURABO Corporation, "Mazerustar KK-250") to prepare a mixture for evaluation. The mixture for evaluation was applied to a 5 mm thick glass plate using an applicator set to a wet thickness of 250 μm, and then heated at 60°C for 30 minutes, 90°C for 10 minutes, 150°C for 30 minutes, and 200°C for 30 minutes to remove ethyl acetate. The mixture was then cooled to room temperature to obtain a particle-containing film. The relative dielectric constant and dielectric loss tangent of the resulting film were evaluated using a cavity resonance method (measurement frequency: 5.8 GHz). The reduction rate (%) of the dielectric constant and the dielectric loss tangent relative to the measured value of the film containing no particles was calculated using the following formula. The results are shown in Table 2. Reduction rate of dielectric constant [%] = 100 - (dielectric constant of film containing particles (2)) / (dielectric constant of film containing no particles) x 100 Reduction rate of dielectric loss tangent [%] = 100 - (dielectric loss tangent of film containing particles (2)) / (dielectric loss tangent of film containing no particles) x 100

[0187]

[0188] The hollow resin particles according to an embodiment of the present invention and the hollow resin particles obtained by the production method according to an embodiment of the present invention can be used in various applications such as resin compositions for semiconductor members, coating compositions, heat insulating resin compositions, light diffusing resin compositions, and light diffusing films.

Claims

A hollow resin particle having a shell portion and a hollow portion surrounded by the shell portion, The average particle size is 0.1 μm to 1 μm, The hollow resin particles have a circularity of 0.97 or more and a ratio of coarse particles having a particle diameter of 5 μm or more of less than 5% by number. Hollow resin particles. 　 the shell portion contains a polymer (P) obtained by the reaction of a monomer component (M) containing a crosslinkable monomer, 2. The hollow resin particle according to claim 1, wherein the content of the crosslinkable monomer in the monomer component (M) is 20% by weight to 100% by weight. 　 the monomer component (M) contains a monofunctional monomer, The hollow resin particle according to claim 2 , wherein the content of the monofunctional monomer in the monomer component (M) is 80% by weight or less. 　 The hollow resin particles according to claim 1, having a hollowness of 20% or more.

2. The hollow resin particle according to claim 1, which has a dielectric loss tangent of less than 0.01 at a measurement frequency of 10 GHz. 　 The hollow resin particle according to claim 5 , wherein the dielectric loss tangent is 0.0030 or less.

2. The hollow resin particles according to claim 1, which have a relative dielectric constant of less than 2.0 at a measurement frequency of 10 GHz.

2. The hollow resin particles according to claim 1, wherein the hollow resin particles have a circularity of 0.80 or more and a proportion of coarse particles having a particle diameter of 5 μm or more is less than 5% by number. 　 The hollow resin particles according to claim 1 , which are used in a resin composition for a semiconductor member. 　 A dispersion containing the hollow resin particles according to claim 1.

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