Hollow resin particles and uses of same

Abstract

The present invention provides hollow resin particles which are not likely to be crushed even when mixed and kneaded with inorganic particles in a resin composition, and which can exhibit excellent low dielectric characteristics. The present invention also provides uses of the hollow resin particles.　Hollow resin particles according to an embodiment of the present invention each have a shell part and one hollow part that is surrounded by the shell part. The shell part contains an aromatic polymer (P1) and a non-crosslinkable polymer (P2), the aromatic polymer (P1) is obtained by a reaction of a monomer component (M) that contains an aromatic monofunctional monomer (a) and an aromatic crosslinkable monomer (b), the percentage of hollowness is 20% to 45%, and the residual ratio of hollowness after a dispersion test is 85% or more.

Description

Hollow resin particles and their uses

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

[0002] In recent years, with the increase in the amount of information processed and the communication speed of various electronic devices, there has been rapid progress in packaging technologies such as higher integration of the mounted semiconductor devices, higher density wiring, and multi-layering.In order to increase the transmission speed of high-frequency signals and reduce loss during signal transmission, resin compositions for semiconductor members used in semiconductor devices are required to use insulating resins with low relative dielectric constants and dielectric loss tangents.

[0003] In response to such demands, a technology has been reported in which hollow resin particles, each having a shell portion and a hollow portion surrounded by the shell portion, are mixed into the insulating resin to introduce air space into the insulating resin, thereby achieving a low dielectric constant and a low dielectric loss tangent.

[0004] Known hollow resin particles include, for example, hollow particles having a shell containing an acrylic resin and a hollow portion surrounded by the shell, with a void remaining rate of 80% or more during a press test (Patent Document 1), hollow particles having a shell containing an acrylic resin and a hollow portion surrounded by the shell, with a void rate of 50% to 90% (Patent Document 2), and hollow particles having a shell containing an acrylic resin and a hollow portion surrounded by the shell, with a void rate of 50% or more (Patent Document 3).

[0005] International Publication No. 2023 / 127624 International Publication No. 2021 / 112110 International Publication No. 2022 / 071275

[0006] Acrylic resins have a high relative permittivity and dielectric loss tangent, which deteriorates low dielectric properties. For this reason, the hollow particles described in Patent Documents 1 to 3 are difficult to apply to recent semiconductor devices that process high-frequency signals.

[0007] On the other hand, in resin compositions used as encapsulants for semiconductor chips, inorganic particles such as silica are often added to insulating resins to enhance functionality. When such resin compositions contain hollow resin particles, there is a problem that the hollow resin particles are crushed during kneading to produce molded articles from the resin composition due to the high kneading shear caused by the presence of inorganic particles that are harder than the resin. Such crushing of hollow resin particles can lead to the risk of not achieving the desired low dielectric properties or the deterioration of the flowability of the resin composition.

[0008] An object of the present invention is to provide hollow resin particles that are resistant to crushing even when kneaded together with inorganic particles in a resin composition and that can exhibit excellent low dielectric properties, and also to provide uses for such hollow resin particles.

[0009] [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, the shell portion comprising an aromatic polymer (P1) and a non-crosslinkable polymer (P2), the aromatic polymer (P1) being obtained by the reaction of a monomer component (M) comprising an aromatic monofunctional monomer (a) and an aromatic crosslinkable monomer (b), the hollow portion having a hollow ratio of 20% to 45% and a residual hollow ratio of 85% or more after a dispersion test. [2] In the hollow resin particles described in [1] above, the monomer component (M) may comprise at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester monomer (d). [3] The hollow resin particles described in [1] or [2] above may have a volume average particle diameter of 2.0 μm to 15.0 μm. [4] In the hollow resin particles according to any one of [1] to [3] above, the aromatic monofunctional monomer (a) may be at least one selected from the group consisting of styrene and ethylvinylbenzene. [5] In the hollow resin particles according to any one of [1] to [4] above, the aromatic crosslinkable monomer (b) may be divinylbenzene. [6] In the hollow resin particles according to any one of [2] to [5] above, the hydrophilic monofunctional monomer (c) may be represented by general formula (1) or general formula (2). In general formula (1), R 1 represents H or CH3, R 2 represents H, an alkyl group, or a phenyl group, and R 3 represents an alkanediyl group having 2 to 18 carbon atoms, and m is R 3 the average number of moles of oxyalkylene groups represented by —O is 1 to 100, and m R 3 are independent of each other. In general formula (2), R 4 represents H or CH3, R 5 represents an alkanediyl group having 1 to 10 carbon atoms or an alkenediyl group having 2 to 10 carbon atoms, R 6 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 5 , X, R 6are independent of each other. [7] In the hollow resin particle according to any one of [1] to [6] above, the content of the aromatic crosslinkable monomer (b) may be 10% by weight to 60% by weight relative to the total amount of the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b). [8] In the hollow resin particle according to any one of [2] to [7] above, the content of the hydrophilic monofunctional monomer (c) may be 0.1% by weight to 5.0% by weight relative to the total amount of the aromatic monofunctional monomer (a), the aromatic crosslinkable monomer (b), the hydrophilic monofunctional monomer (c), and the phosphate ester monomer (d). [9] In the hollow resin particle according to any one of [1] to [8] above, the non-crosslinkable polymer (P2) may be at least one selected from the group consisting of olefin-based polymers and styrene-based polymers.

[10] In the hollow resin particles according to any one of [1] to [9] above, the content of the aromatic polymer (P1) in the shell portion may be 60% to 99% by weight.

[11] In the hollow resin particles according to any one of [1] to

[10] above, the content of the non-crosslinkable polymer (P2) in the shell portion may be 1% to 40% by weight.

[12] The hollow resin particles according to any one of [1] to

[11] above may be used in a resin composition for a semiconductor member.

[13] A resin composition for a semiconductor member according to an embodiment of the present invention comprises the hollow resin particles according to any one of [1] to

[11] above.

[14] The resin composition for a semiconductor member according to

[13] above may be used as an encapsulant for a semiconductor chip.

[0010] According to an embodiment of the present invention, hollow resin particles that are resistant to crushing even when kneaded together with inorganic particles in a resin composition and that can exhibit excellent low dielectric properties can be provided, and uses of such hollow resin particles can be provided.

[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", the expression "(meth)allyl" means "allyl and / or methallyl", and the expression "(meth)acrolein" means "acrolein and / or methacrolein". Furthermore, in this specification, the expression "acid (salt)" means "acid and / or its salt". Examples of salts include alkali metal salts and alkaline earth metal salts, and specific examples include sodium salts and potassium salts.

[0013] Hollow Resin Particles According to an embodiment of the present invention, hollow resin particles have a shell portion and a hollow portion surrounded by the shell portion. Here, "hollow" refers to a state in which the interior is filled with a substance other than resin, such as a gas or liquid, and preferably refers to a state in which the interior is filled with a gas, in order to further exhibit the effects of the present invention.

[0014] In the hollow resin particles according to an embodiment of the present invention, the hollow portion is a single hollow portion, and unlike a porous structure, it has a single hollow structure consisting of a single hollow region. Since 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, since the hollow portion is a single hollow portion, penetration of the hollow portion into the substrate or the like may be effectively prevented.

[0015] The hollow resin particles according to an embodiment of the present invention typically have a hollowness of 20% to 45%, but may also be 22% to 43%, 24% to 41%, or 25% to 40%. When the hollowness of the hollow resin particles is within the above range, the hollow resin particles are less likely to be crushed when kneaded with inorganic particles in a resin composition, and excellent low dielectric properties can be exhibited. When the hollowness of the hollow resin particles is outside the above range, the hollow resin particles may be crushed when kneaded with inorganic particles in a resin composition, which may result in failure to achieve the desired low dielectric properties and may also deteriorate the fluidity of the resin composition.

[0016] The hollow resin particles according to an embodiment of the present invention typically have a hollow residual ratio of 85% or more, or may be 86% or more, 87% or more, 88% or more, 89% or more, or even 90% or more after a dispersion test described in detail below. The upper limit of the hollow residual ratio is, for example, 100% or less. The dispersion test described in detail below is a model test in which hollow resin particles are kneaded together with inorganic particles in a resin composition, and this dispersion test indicates the degree to which the hollow portions of the hollow resin particles remain. Therefore, the higher the hollow residual ratio after the dispersion test, the more resistant the hollow resin particles are to crushing when kneaded together with inorganic particles in a resin composition, and the more likely they are to exhibit excellent low dielectric properties.

[0017] The volume average particle diameter of the hollow resin particles according to an embodiment of the present invention is preferably 2.0 μm to 15.0 μm, or may be 2.5 μm to 12.0 μm, or may be 3.0 μm to 10.0 μm. If the volume average particle diameter of the hollow resin particles is less than 2.0 μm, the thickness of the shell portion becomes relatively thin, and there is a risk that the shell portion will be crushed when the hollow resin particles are kneaded together with inorganic particles in a resin composition. If the average particle diameter of the hollow resin particles is greater than 15.0 μm, there is a risk that phase separation between the polymer and the solvent produced by polymerization of the monomer component during suspension polymerization to form the shell portion will be difficult to occur, which may make it difficult to form the shell portion.

[0018] The surface of the hollow resin particles according to the embodiment of the present invention is preferably non-porous. The specific surface area of ​​the hollow resin particles according to the embodiment of the present invention is preferably 0.1 m 2 / g to 5m 2 / g, and 0.3m 2 / g to 3m 2 When the hollow resin particles according to the embodiment of the present invention have a specific surface area within the above range, the resin can be prevented from penetrating into the hollow portions when added to a resin composition.

[0019] The hollow resin particles according to the embodiment of the present invention preferably have a dielectric constant (Dk) of 2.1 or less at a frequency of 10 GHz, and may be 2.0 or less, or 1.9 or less. When the dielectric constant (Dk) at a frequency of 10 GHz is within the above range, the hollow resin particles according to the embodiment of the present invention can exhibit excellent low dielectric properties.

[0020] The hollow resin particles according to an embodiment of the present invention preferably have a dielectric loss tangent (Df) at a frequency of 10 GHz of 0.0050 or less, or alternatively, 0.0045 or less, 0.0040 or less, 0.0035 or less, or 0.0030 or less. When the dielectric loss tangent (Df) 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.

[0021] <Shell Portion> The shell portion typically contains an aromatic polymer (P1) and a non-crosslinkable polymer (P2). When the shell portion contains an aromatic polymer (P1) and a non-crosslinkable polymer (P2), the effects of the present invention can be exhibited.

[0022] The content of the aromatic polymer (P1) in the shell is preferably 60% by weight to 99% by weight, may be 70% by weight to 97% by weight, may be 80% by weight to 96% by weight, or may be 85% by weight to 95% by weight, in order to further exhibit the effects of the present invention.

[0023] The content of the non-crosslinkable polymer (P2) in the shell portion is preferably 1% by weight to 40% by weight, may be 3% by weight to 30% by weight, may be 4% by weight to 20% by weight, or may be 5% by weight to 15% by weight, in terms of being able to further exhibit the effects of the present invention.

[0024] The shell portion may contain any appropriate other component other than the aromatic polymer (P1) and the non-crosslinkable polymer (P2), as long as the effects of the present invention are not impaired. The other component may be one kind or two or more kinds.

[0025] The aromatic polymer (P1) may be of one kind or of two or more kinds.

[0026] The aromatic polymer (P1) is typically obtained by the reaction of a monomer component (M) containing an aromatic monofunctional monomer (a) and an aromatic crosslinkable monomer (b).

[0027] The content ratio of the total amount of the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b) in the total amount of the monomer component (M) is preferably 50% by weight to 100% by weight, may be 70% by weight to 100% by weight, may be 80% by weight to 100% by weight, may be 90% by weight to 100% by weight, or may be 95% by weight to 100% by weight, in terms of being able to further exhibit the effects of the present invention.

[0028] The content of the aromatic monofunctional monomer (a) relative to the total amount of the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b) is preferably 40% to 90% by weight, or may be 45% to 85% by weight, 50% to 80% by weight, 55% to 80% by weight, or 60% to 80% by weight, in order to further exhibit the effects of the present invention. If the content of the aromatic monofunctional monomer (a) is too high, the crosslink density will be low, which may reduce the strength of the shell portion. If the content of the aromatic monofunctional monomer (a) is too low, unreacted reactive sites will remain, which may adversely affect the sufficient expression of low dielectric properties.

[0029] The content of the aromatic crosslinkable monomer (b) relative to the total amount of the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b) is preferably 10% to 60% by weight, but may also be 15% to 55% by weight, 20% to 50% by weight, or 20% to 45% by weight, in order to further demonstrate the effects of the present invention. If the content of the aromatic crosslinkable monomer (b) is too high, unreacted reactive sites may remain, which may adversely affect the sufficient development of low dielectric properties. If the content of the aromatic crosslinkable monomer (b) is too low, the crosslink density may be low, which may reduce the strength of the shell portion.

[0030] The monomer component (M) may contain at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester monomer (d). That is, the monomer component (M) may contain, in addition to the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b), at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester monomer (d).

[0031] The content ratio of the total amount of the aromatic monofunctional monomer (a), the aromatic crosslinkable monomer (b), the hydrophilic monofunctional monomer (c), and the phosphate ester monomer (d) in the total amount of the monomer component (M) is preferably 50% by weight to 100% by weight, may be 70% by weight to 100% by weight, may be 80% by weight to 100% by weight, may be 90% by weight to 100% by weight, or may be 95% by weight to 100% by weight, in terms of being able to further exhibit the effects of the present invention.

[0032] When the monomer component (M) contains at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester-based monomer (d), the content ratio of the hydrophilic monofunctional monomer (c) relative to the total amount of the aromatic monofunctional monomer (a), the aromatic crosslinkable monomer (b), the hydrophilic monofunctional monomer (c), and the phosphate ester-based monomer (d) is preferably 0.1% by weight to 5.0% by weight, may be 0.3% by weight to 4.0% by weight, may be 0.4% by weight to 3.0% by weight, or may be 0.5% by weight to 2.0% by weight, in terms of being able to further exhibit the effects of the present invention.

[0033] When the monomer component (M) contains at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester monomer (d), the content ratio of the phosphate ester monomer (d) relative to the total amount of the aromatic monofunctional monomer (a), the aromatic crosslinkable monomer (b), the hydrophilic monofunctional monomer (c), and the phosphate ester monomer (d) is preferably 0.01% by weight to 5.00% by weight, may be 0.05% by weight to 3.00% by weight, may be 0.08% by weight to 1.00% by weight, may be 0.10% by weight to 0.50% by weight, may be 0.12% by weight to 0.45% by weight, may be 0.14% by weight to 0.45% by weight, or may be 0.16% by weight to 0.45% by weight, in terms of being able to further exhibit the effects of the present invention.

[0034] The aromatic monofunctional monomer (a) may be of one type only, or of two or more types.

[0035] As the aromatic monofunctional monomer (a), any appropriate aromatic monofunctional monomer can be used as long as it is a monofunctional aromatic monomer and does not impair the effects of the present invention. Examples of such aromatic monofunctional monomers (a) include styrene, ethylvinylbenzene, α-methylstyrene, vinyltoluene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, vinylbiphenyl, and vinylnaphthalene, from the viewpoint of being able to further exhibit the effects of the present invention and from the viewpoint of reactivity. The aromatic monofunctional monomer (a) is preferably at least one selected from the group consisting of styrene and ethylvinylbenzene.

[0036] The aromatic crosslinkable monomer (b) may be used alone or in combination of two or more kinds.

[0037] As the aromatic crosslinkable monomer (b), any appropriate aromatic crosslinkable monomer can be used as long as it is an aromatic monomer having crosslinkability, as long as it does not impair the effects of the present invention. Examples of such aromatic crosslinkable monomer (b) include divinylbenzene, divinylnaphthalene, and diallyl phthalate, which can further demonstrate the effects of the present invention. In terms of further demonstrating the effects of the present invention and reactivity, divinylbenzene is preferred as the aromatic crosslinkable monomer (b).

[0038] The hydrophilic monofunctional monomer (c) may be of one type only, or of two or more types.

[0039] As the hydrophilic monofunctional monomer (c), any appropriate hydrophilic monofunctional monomer can be adopted as long as it does not impair the effects of the present invention. In terms of being able to further exhibit the effects of the present invention, the hydrophilic monofunctional monomer (c) is preferably represented by general formula (1) or general formula (2).

[0040]

[0041]

[0042] In general formula (1), R 1 represents H or CH3.

[0043] In general formula (1), R 2 represents H, an alkyl group, or a phenyl group.

[0044] In general formula (1), R 3 represents an alkanediyl group having 2 to 18 carbon atoms, preferably an alkanediyl group having 2 to 8 carbon atoms, and may also be an alkanediyl group having 2 to 4 carbon atoms. The alkanediyl group may be linear, branched, or cyclic.

[0045] 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.

[0046] In general formula (1), R 3 -O is an oxyalkylene group having 2 to 18 carbon atoms, preferably an oxyalkylene group having 2 to 8 carbon atoms, and may also be an oxyalkylene group having 2 to 4 carbon atoms. 3 When —O is at least two or more selected from an oxyethylene group, an oxypropylene group, and an oxybutylene group, R 3 The addition form of -O may be any of random addition, block addition, and alternating addition. Note that the addition form referred to here means the form itself, and does not mean that it must be obtained by an addition reaction.

[0047] In general formula (1), R 3 —O is at least one selected from the group consisting of an oxyethylene group, an oxypropylene group, and an oxybutylene group (typically, an oxytetramethylene group), in that the effects of the present invention can be more effectively exhibited.

[0048] In the general formula (1), m is R 3represents the average number of moles added (sometimes referred to as "chain length") of oxyalkylene groups represented by -O. m is a number from 1 to 100, and may be a number from 1 to 40, a number from 2 to 30, a number from 3 to 20, a number from 4 to 18, or a number from 5 to 15. When m is within the above range, the effects of the present invention can be more effectively exhibited.

[0049] In the general formula (1), m R 3 are independent of each other. In general formula (1), R 3 When there are two or more types of —O, for example, when it consists of an oxyethylene group (C2H4O) and an oxypropylene group (C3H6O), m is the sum of the average number of moles of the oxyalkylene groups added. 3 -O) m - is - [(C2H4O) p (C3H6O) q ]- (as mentioned above, the addition may be in the form of random addition, block addition, or alternating addition), then m=p+q.

[0050] Examples of the hydrophilic monofunctional monomer (c) represented by general formula (1) include methoxypolyethylene glycol methacrylate, ethoxypolyethylene glycol methacrylate, propoxypolyethylene glycol methacrylate, butoxypolyethylene glycol methacrylate, hexaoxypolyethylene glycol methacrylate, octoxypolyethylene glycol polypropylene glycol methacrylate, lauroxypolyethylene glycol methacrylate, stearoxypolyethylene glycol methacrylate, phenoxypolyethylene glycol polypropylene glycol methacrylate, methoxypolyethylene glycol acrylate, polyethylene glycol monomethacrylate, polypropylene glycol monomethacrylate, polyethylene glycol propylene glycol monomethacrylate, polyethylene glycol tetramethylene glycol monomethacrylate, propylene glycol polybutylene glycol monomethacrylate, monoethylene glycol monoacrylate, and polypropylene glycol monoacrylate.

[0051] The hydrophilic monofunctional monomer (c) represented by the general formula (1) may be a commercially available product, such as the "Blenmer" series manufactured by NOF Corporation.

[0052] In general formula (2), R 4 represents H or CH3.

[0053] In general formula (2), R 5 represents an alkanediyl group having 1 to 10 carbon atoms or an alkenediyl group having 2 to 10 carbon atoms. The alkanediyl group preferably has 2 to 6 carbon atoms, and may have 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 may have 2 to 4 carbon atoms. The alkenediyl group may be linear, branched, or cyclic.

[0054] R 5 With regard to R, examples of the alkanediyl group include those mentioned above. 5 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.

[0055] In general formula (2), R 6 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. The alkanediyl group preferably has 2 to 6 carbon atoms, and may have 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 may have 2 to 4 carbon atoms. The alkenediyl group may be linear, branched, or cyclic.

[0056] R 6 With regard to R, examples of the alkanediyl group include those mentioned above. 6 With regard to the above, examples of the alkenediyl group include those mentioned above.

[0057] In general formula (2), X represents a single bond, an ester bond, an ether bond, or a carbonyl group. 5 -O-CO-R 6 or R 5 -CO-O-R 6 The structure may be:

[0058] In the general formula (2), n represents a number from 1 to 5, and n R 5 , X, R 6 are independent of each other.

[0059] Examples of the hydrophilic monofunctional monomer (c) represented by general formula (2) 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.

[0060] The hydrophilic monofunctional monomer (c) represented by the general formula (2) may be a commercially available product, such as "Light Ester HO-MS (N)" manufactured by Kyoeisha Chemical Co., Ltd.

[0061] The phosphate ester-based monomer (d) may be used alone or in combination of two or more kinds.

[0062] As the phosphate ester-based monomer (d), any appropriate phosphate ester-based monomer may be adopted as long as the effects of the present invention are not impaired. In order to further demonstrate the effects of the present invention, a compound having a phosphate ester structure and a radical-reactive group may preferably be adopted as the phosphate ester-based monomer (d). In order to further demonstrate the effects of the present invention, a compound represented by general formula (3) is preferably used as such a compound.

[0063]

[0064] In formula (3), R 7 represents a methyl group or a hydrogen atom.

[0065] In formula (3), a is 0 or 1, b is 0 to 300, c is 0 or 1, and d is 1 to 300. In formula (3), p represents 1 to 3.

[0066] In formula (3), R 8 is a linear or branched alkylene group having 1 to 50 carbon atoms, preferably a linear or branched alkylene group having 1 to 40 carbon atoms, and may be a linear or branched alkylene group having 1 to 30 carbon atoms, a linear or branched alkylene group having 1 to 25 carbon atoms, a linear or branched alkylene group having 1 to 20 carbon atoms, a linear or branched alkylene group having 1 to 15 carbon atoms, a linear or branched alkylene group having 1 to 10 carbon atoms, a linear or branched alkylene group having 1 to 8 carbon atoms, a linear or branched alkylene group having 1 to 6 carbon atoms, or a linear or branched alkylene group having 1 to 4 carbon atoms.

[0067] In formula (3), R 9 is a linear or branched alkylene group having 1 to 50 carbon atoms, preferably a linear or branched alkylene group having 1 to 40 carbon atoms, and may be a linear or branched alkylene group having 1 to 30 carbon atoms, a linear or branched alkylene group having 1 to 25 carbon atoms, a linear or branched alkylene group having 1 to 20 carbon atoms, a linear or branched alkylene group having 1 to 15 carbon atoms, a linear or branched alkylene group having 1 to 13 carbon atoms, a linear or branched alkylene group having 1 to 10 carbon atoms, or a linear or branched alkylene group having 1 to 8 carbon atoms.

[0068] In formula (3), b is preferably 0 to 100, may be 0 to 50, may be 0 to 10, may be 0 to 5, or may be 0 or 1.

[0069] In formula (3), d is preferably 1 to 100, and may be 1 to 50, 1 to 30, 1 to 10, 1 to 5, or 1 to 3.

[0070] The phosphate ester monomer (d) may be a commercially available product, such as "KAYAMER (registered trademark) PM-21" (manufactured by Nippon Kayaku Co., Ltd.) from the viewpoint of compatibility.

[0071] The monomer component (M) may contain any other appropriate monomer other than the aromatic monofunctional monomer (a), the aromatic crosslinkable monomer (b), the hydrophilic monofunctional monomer (c), and the phosphate ester monomer (d), as long as the effects of the present invention are not impaired. The other monomer may be one type only, or two or more types.

[0072] The non-crosslinkable polymer (P2) may be one kind or two or more kinds.

[0073] When the shell portion contains the non-crosslinkable polymer (P2), the effects of the present invention can be exhibited, and phase separation within the polymerized oil droplets during suspension polymerization can be promoted, making it easier to form uniform particles, and as a result, excellent low dielectric properties and uniform low dielectric properties can be exhibited.

[0074] As the non-crosslinkable polymer (P2), any appropriate non-crosslinkable polymer (P2) can be used as long as it does not impair the effects of the present invention. As such a non-crosslinkable polymer (P2), a non-crosslinkable polymer having no carboxyl group is preferred, and examples thereof include paraffin, an olefin-based polymer, a styrene-based polymer, and a (meth)acrylic acid ester-based polymer, and at least one selected from the group consisting of an olefin-based polymer and a styrene-based polymer is preferred.

[0075] The content of the non-crosslinkable polymer (P2) in the shell portion is preferably 0 to 40% by weight, or may be 3 to 30% by weight, or may be 5 to 20% by weight, in order to further exhibit the effects of the present invention. If the content of the non-crosslinkable polymer (P2) in the shell portion is too high, there is a risk that excellent low dielectric properties may not be exhibited or that uniform low dielectric properties may not be exhibited.

[0076] When the non-crosslinkable polymer (P2) is an olefin-based polymer, the content of the non-crosslinkable polymer (P2) in the shell is particularly preferably 7% by weight to 20% by weight, and may be 7% by weight to 15% by weight, in order to further exhibit the effects of the present invention.

[0077] When the non-crosslinkable polymer (P2) is a styrene-based polymer, the content of the non-crosslinkable polymer (P2) in the shell is particularly preferably 5% by weight to 15% by weight, and may be 5% by weight to 12% by weight, in order to further exhibit the effects of the present invention.

[0078] Examples of paraffin include paraffin wax and liquid paraffin.

[0079] Examples of olefin polymers include polyethylene, polypropylene, and poly-α-olefins.

[0080] Examples of styrene polymers include polystyrene, styrene-acrylonitrile copolymers, and acrylonitrile-butadiene-styrene copolymers.

[0081] Examples of the (meth)acrylic acid ester polymer include polymethyl(meth)acrylate, polyethyl(meth)acrylate, polybutyl(meth)acrylate, polypropyl(meth)acrylate, styrene-methyl(meth)acrylate copolymer, styrene-ethyl(meth)acrylate copolymer, styrene-butyl(meth)acrylate copolymer, and styrene-propyl(meth)acrylate copolymer.

[0082] <<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.

[0083] The hollow resin particles according to an embodiment of the present invention are typically prepared by dispersing a monomer component (M) containing an aromatic monofunctional monomer (a) and an aromatic crosslinkable monomer (b), a non-crosslinkable polymer (P2), and an oil phase containing an organic solvent in an aqueous phase containing an aqueous medium and at least one selected from the group consisting of a dispersion stabilizer and a surfactant, and then performing suspension polymerization.

[0084] The monomer component (M) may contain at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester monomer (d). That is, the monomer component (M) may contain, in addition to the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b), at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester monomer (d).

[0085] The blending ratio of the monomer component (M) and the non-crosslinkable polymer (P2) in the oil phase is, in weight ratio, preferably (60 to 99):(1 to 40), but may also be (70 to 97):(3 to 30), (80 to 96):(4 to 20), or (85 to 95):(5 to 15).

[0086] 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.

[0087] 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.

[0088] 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).

[0089] 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.

[0090] 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).

[0091] The polymerization initiator may be a polymerization initiator having a 10-hour half-life temperature of 90° C. or less.

[0092] 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).

[0093] 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.

[0094] 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.

[0095] The amount of the aqueous medium used may be any appropriate amount as long as it does not impair the effects of the present invention. Such an amount is, for example, 100 to 2,000 parts by weight, or may be 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.

[0096] Any suitable dispersion stabilizer may be used as the dispersion stabilizer as long as it does not impair the effects of the present invention. The dispersion stabilizer may be one type or two or more types. Examples of such dispersion stabilizers include phosphates such as calcium phosphate, magnesium phosphate, aluminum phosphate, and zinc phosphate; pyrophosphates such as calcium pyrophosphate, magnesium pyrophosphate, aluminum pyrophosphate, and zinc pyrophosphate; poorly water-soluble inorganic compounds such as calcium carbonate, magnesium carbonate, magnesium oxide, colloidal silica, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, calcium metasilicate, calcium sulfate, barium sulfate, and colloidal silica; and water-soluble polymers such as polyvinylpyrrolidone, partially saponified polyvinyl alcohol, polyacrylic acid, carboxymethyl cellulose, and methyl cellulose. Among these, the use of a dispersion stabilizer that is decomposed by acid and dissolved in water (e.g., calcium carbonate, tricalcium phosphate, magnesium hydroxide, magnesium pyrophosphate, and calcium pyrophosphate) is preferred because it allows for easy removal of the dispersion stabilizer after polymerization.

[0097] The amount of the dispersion stabilizer used may be any appropriate amount within a range that does not impair the effects of the present invention. Such an amount is, for example, 0.1 to 20 parts by weight, or may be 0.5 to 10 parts by weight, relative to 100 parts by weight of the oil phase, in order to ensure the fluidity of the suspension while providing excellent dispersibility of droplets of the raw material mixture in the suspension.

[0098] As the surfactant, any appropriate surfactant may be used 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.

[0099] 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 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 phosphate sulfonates; glycerol borate fatty acid esters; and polyoxyethylene glycerol fatty acid esters. The anionic surfactant may be used alone or in combination of two or more kinds.

[0100] 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.

[0101] 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.

[0102] Examples of the zwitterionic surfactant include lauryl dimethylamine oxide, phosphate surfactants, and phosphite surfactants. Only one type of zwitterionic surfactant may be used, or two or more types may be used.

[0103] As the surfactant, a reactive surfactant having a vinyl group may be used. 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 aromatic polymer (P1), so that the surfactant can be effectively unevenly distributed on the particle surface in suspension polymerization, and the surfactant effect can be improved. Therefore, an excellent surfactant effect can be obtained, and the occurrence of particle aggregation and coalescence during production can be suppressed, the by-production of non-standard particles can be reduced, and more uniform low dielectric properties can be exhibited.

[0104] Examples of reactive surfactants having a vinyl group include anionic surfactants having a vinyl group and nonionic surfactants having a vinyl group.

[0105] Examples of anionic surfactants having a vinyl group include polyoxyethylene-1-(allyloxymethyl) alkyl ether sulfate ammonium, polyoxyethylene styrenated propenyl phenyl ether sulfate 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.

[0106] 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.

[0107] Commercially available polyoxyethylene styrenated propenyl phenyl ether ammonium sulfate products include, for example, trade names "Aqualon AR-10," "Aqualon AR-20," and "Aqualon AR-1025" (a 25 wt % aqueous solution of "Aqualon AR-10") manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.

[0108] An example of a commercially available polyoxyalkylene alkenyl ether ammonium sulfate is "Latemul PD-104" manufactured by Kao Corporation.

[0109] 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.

[0110] An example of a commercially available polyoxypropylene allyl ether phosphate ester is "ADEKA REASOAP PP-70" manufactured by ADEKA Corporation.

[0111] An example of a commercially available product of bis(polyoxyethylene phenyl ether) methacrylate sulfate is "Antox MS-60" manufactured by Nippon Nyukazai Co., Ltd.

[0112] Examples of nonionic surfactants having a vinyl group include polyoxyethylene styrenated propenyl phenyl ether, polyoxyethylene-1-(allyloxymethyl) alkyl ether, and polyoxyalkylene alkenyl ether.

[0113] 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.

[0114] 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."

[0115] 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.

[0116] The surfactant may be used in any appropriate amount as long as the effects of the present invention are not impaired. Such an amount is, for example, 0.001 to 5 parts by weight, 0.005 to 3 parts by weight, or 0.01 to 1 part by weight, relative to 100 parts by weight of the oil phase.

[0117] 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.

[0118] 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.

[0119] 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.

[0120] Any appropriate method can be adopted as the suspension polymerization method as long as it does not impair the effects of the present invention.

[0121] 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.

[0122] 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.

[0123] Post-heating, which is preferably carried out after polymerization, is a treatment suitable for obtaining hollow resin particles with a high degree of perfection.

[0124] 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.

[0125] 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.

[0126] The slurry obtained by suspension polymerization is subjected to distillation, solvent removal, washing, drying, classification, etc., as required, to obtain hollow resin particles.

[0127] <<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.

[0128] <Resin composition for semiconductor member> The hollow resin particles according to an embodiment of the present invention are resistant to crushing even when kneaded together with inorganic particles in a resin composition, and can exhibit excellent low dielectric properties, and therefore can be suitably used in a resin composition for a semiconductor member.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] <<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.

[0134] Such coating compositions include hollow resin particles according to embodiments of the present invention.

[0135] 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.

[0136] 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.

[0137] 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.

[0138] 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 5% by weight to 50% by weight, or may be 10% by weight to 50% by weight, or more preferably 20% by weight to 40% by weight, based on the total amount of the binder resin (in the case of an emulsion-type aqueous resin, on a solids basis), the at least one selected from the UV-curable resin, and the hollow resin particles according to the embodiment of the present invention.

[0139] 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.

[0140] 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.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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.).

[0146] 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.

[0147] Such a heat insulating resin composition contains hollow resin particles according to an embodiment of the present invention.

[0148] 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.

[0149] The heat insulating resin composition may contain a solvent. Regarding the solvent, the above explanation regarding the coating composition may be applied.

[0150] 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.

[0151] 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.

[0152] 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.

[0153] <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.

[0154] Such a light-diffusing resin composition contains hollow resin particles according to an embodiment of the present invention.

[0155] 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.

[0156] The light-diffusing resin composition may contain a solvent. The above-mentioned explanation of the coating composition may be applied to the solvent.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] <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 therefore can also be suitably used for a light diffusing film.

[0161] Such a light-diffusing film includes hollow resin particles according to an embodiment of the present invention.

[0162] The light diffusion film includes a light diffusion layer formed from the light-diffusing resin composition 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 particle layer, a conductive metal oxide particle layer, and a primer layer.

[0163] 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).

[0164] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" means "parts by weight" and "%" means "% by weight."

[0165] <Volume Average Particle Diameter> The volume average particle diameter of the resin particles was measured using a measuring device commercially available from Beckman Coulter under the trade name "Coulter Multisizer 4e." The measurement was performed using an aperture calibrated according to the Multisizer (registered trademark) 4e user's manual published by Beckman Coulter. The aperture used for the measurement was selected appropriately by selecting an aperture having a size of 50 μm when the assumed volume average particle diameter of the resin particles to be measured was 1 μm or more and 10 μm or less, selecting an aperture having a size of 100 μm when the assumed volume average particle diameter of the resin particles to be measured was more than 10 μm but 30 μm or less, and selecting an aperture having a size of 280 μm when the assumed volume average particle diameter of the resin particles to be measured was more than 30 μm but 90 μm or less. If the volume average particle diameter after measurement differed from the assumed volume average particle diameter, the aperture was changed to one having an appropriate size and the measurement was performed again. When an aperture having a size of 50 μm was selected, Current (aperture current) was set to −800 and Gain was set to 4; when an aperture having a size of 100 μm was selected, Current (aperture current) was set to −1600 and Gain was set to 2; and when apertures having sizes of 280 μm and 400 μm were selected, Current (aperture current) was set to −3200 and Gain was set to 1. The measurement sample was prepared by dispersing 0.1 g of resin particles in 10 mL of an aqueous solution of 0.1 wt% nonionic surfactant (manufactured by Kao Corporation, trade name "Pelex SS-H") using a touch mixer (manufactured by Yamato Scientific Co., Ltd., "Touchmixer MT-31") and an ultrasonic cleaner (manufactured by Vervoclear, Inc., "Ultrasonic Cleaner VS-150") to prepare a dispersion. A beaker filled with ISOTON (registered trademark) II (manufactured by Beckman Coulter, Inc., measurement electrolyte) was placed in the measurement section of a Coulter Multisizer 4e, and the dispersion was added dropwise while gently stirring the contents of the beaker. After adjusting the reading of the densitometer on the Coulter Multisizer 4e main screen to 5% to 10%, measurement was started.During the measurement, the contents of the beaker were gently stirred to prevent air bubbles from being introduced, and the measurement was stopped when 100,000 resin particles were measured. The volume-average particle size of the resin particles was taken as the arithmetic mean value in the volume-based particle size distribution of 100,000 particles. The coefficient of variation (CV value) was calculated using the following formula: Coefficient of variation (CV value) (%) = standard deviation × 100 / (volume-average particle size of primary particles).

[0166] <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 The mixture was degassed and stirred using a degassing mixer (manufactured by Thinky Corporation, trade 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 (4). The apparent density of the hollow resin particles containing air was calculated from the densities of the mixture and the dispersion medium and their respective weight proportions in the mixture using the following formula (5), and the hollow fraction of the hollow resin particles was calculated from the apparent density and the density of the shell. In equation (4), 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 (5), 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.

[0167] <Hollow Residual Rate After Dispersion Test> The dispersion test and measurement of the hollow residual rate of hollow resin particles after the dispersion test were performed as follows. Hollow resin particles, inorganic particles (silica particles manufactured by Denka, product name "FB-5SDX"), and a dispersion medium were weighed out so that the ratio of hollow resin particles was 8 vol%, silica particles was 15 vol%, and the dispersion medium (ARUFON UP-1020) was 77 vol%. To 100 vol% of this mixture, 50 vol% of zirconia beads with a diameter of 0.5 mm and 20 vol% of zirconia beads with a diameter of 5 mm were added. The mixture was dispersed in a ball mill for 24 hours, and the zirconia beads were then removed to prepare a mixture for evaluation. The mixture for evaluation was filled into the measurement cell of a vibration density meter, and the frequency of the mixture in the measurement cell was measured. The density of the mixture after the dispersion test was calculated using the above formula (4). Next, the apparent density of the hollow resin particles was calculated from the densities of the dispersion medium and silica particles and their respective weight proportions in the mixture using the following formula (6), the hollow ratio of the hollow resin particles was calculated from the apparent density and the density of the shell, and the hollow residual ratio of the hollow resin particles was calculated using the following formula (7). In formula (6), ρ p' is the apparent density [g / cm 3 ] of the hollow resin particles after the dispersion test 3 ], ρ i is the density of the inorganic particles [g / cm 3 ], x i represents the weight percentage of inorganic particles in the sample.

[0168] The dielectric properties of the hollow resin particles were measured using a dielectric constant measurement device (ADMS01Nc series, manufactured by AET Co., Ltd.) The relative permittivity (Dk) and dielectric loss tangent (Df) of the hollow resin particles were calculated based on the perturbation theory using a resonator at a frequency of 10 GHz, a measurement environment temperature of 23°C, and a relative humidity of 51±1% or less.

[0169] <Observation of Internal Structure of Resin Particles> Hollow resin particles were processed using a sample cross-section preparation device (manufactured by JEOL Ltd., product name "IB-19500CP"), and the cross-sections of the hollow resin particles were observed using a scanning electron microscope (SEM) (manufactured by Hitachi High-Technologies Corporation, product name "SU-3800") at magnifications of 500 to 3000 times.

[0170] <Raw materials used> The raw materials used are as follows.

[0171] [Aromatic Monofunctional Monomer (a)] Styrene

[0172] [Aromatic crosslinkable monomer (b)] Divinylbenzene (DVB) 810 (Nippon Steel Chemical & Material Co., Ltd., 81% by weight content, 19% by weight is ethylvinylbenzene (EVB))

[0173] [Hydrophilic monofunctional monomer (c)] Compound corresponding to general formula (1): polyethylene glycol propylene glycol monomethacrylate (manufactured by NOF Corporation, trade name "BLEMMER 50PEP-300"; in general formula (1), R 1 = CH3, R 2 = H, (R 3 -O) m = [(C2H4O) 3.5 (C3H6O) 2.5 ], random addition form) Compound corresponding to general formula (2): 2-methacryloyloxyethyl succinic acid (manufactured by Kyoeisha Chemical Co., Ltd., trade name "Light Ester HO-MS (N)"; in general formula (2), R 4 = CH3, R 5 = CH2CH2, R 6 =CH2CH2, X=-OC(=O)-, n=1)

[0174] [Phosphate ester monomer (d)] KAYAMER (registered trademark) PM-21 (manufactured by Nippon Kayaku Co., Ltd.)

[0175] [Non-crosslinked polymer (P2)] Non-crosslinked polystyrene (non-crosslinked PS) Polyolefin wax (manufactured by Nucera Solutions, trade name "VYBAR260")

[0176] [Organic solvent] Heptane

[0177] [Surfactant] Bis(polyoxyethylene phenyl ether) methacrylate sulfate (manufactured by Nippon Nyukazai Co., Ltd., trade name "Antox MS-60")

[0178] [Polymerization initiator] 2,2'-azobis(2,4-dimethylvaleronitrile) (ABN-V) Azobisisobutyronitrile (AIBN)

[0179] [Aqueous medium] Ion-exchanged water

[0180] [Example 1] 300 parts by weight of ion-exchanged water and 2.5 parts by weight of magnesium pyrophosphate as a dispersion stabilizer were supplied to a polymerization vessel equipped with a stirrer, a thermometer, and a cooling mechanism to prepare an aqueous phase. Separately, the aromatic monofunctional monomer (a), aromatic crosslinkable monomer (b), hydrophilic monofunctional monomer (c), phosphate ester monomer (d), non-crosslinkable polymer (P2), organic solvent, and polymerization initiator shown in Table 1 were uniformly mixed to prepare an oil phase. The oil phase was supplied to the aqueous phase in the polymerization vessel and stirred for 10 minutes at a rotation speed of 8,000 rpm using a homomixer (manufactured by Primix Corporation, trade name "T.K. Homomixer MARK II 2.5 Type"), followed by emulsification using a high-pressure emulsifier NVR (manufactured by Yoshida Kikai Kogyo Co., Ltd., model "EM055-P20-0600-Exp") at an inlet treatment pressure of 15 MPa and an outlet pressure of 1 MPa, to produce a dispersion in which droplets of the oil phase were dispersed in the aqueous phase. After purging the interior of the polymerization vessel with nitrogen gas, the dispersion was heated to 55°C. While stirring the dispersion at 55°C, the raw material monomers were polymerized for 4 hours. During the polymerization reaction, 2 hours after the exothermic peak was confirmed, the dispersion was heated to 80°C and maintained at this temperature for 4 hours. After removing the organic solvent by distillation, the dispersion was cooled to obtain a slurry containing hollow resin particles. Hydrochloric acid was added to the resulting slurry to decompose the magnesium pyrophosphate, and the resulting slurry was then subjected to suction filtration to separate and reduce the amount of water, producing a cake containing hollow resin particles. The cake was dried in a vacuum oven at 80°C to obtain hollow resin particles (1). The results are shown in Table 1.

[0181] Examples 2 to 10 Hollow resin particles (2) to (10) were obtained in the same manner as in Example 1, except that the various formulations were changed as shown in Table 1. In Examples 6, 7, and 10, the aqueous phase was prepared by feeding 300 parts by weight of ion-exchanged water, 2.5 parts by weight of magnesium pyrophosphate as a dispersion stabilizer, and the amount of bis(polyoxyethylene phenyl ether) methacrylate sulfate salt (trade name "Antox MS-60", manufactured by Nippon Nyukazai Co., Ltd.) as a surfactant into a polymerization vessel equipped with a stirrer, a thermometer, and a cooling mechanism. The results are shown in Table 1.

[0182] Comparative Examples 1 to 6 Hollow resin particles (C1) to (C6) were obtained in the same manner as in Example 1, except that the various formulations were changed as shown in Table 1. The results are shown in Table 1.

[0183]

[0184] The hollow resin particles according to an embodiment of the present invention can be used in a variety of applications, such as resin compositions for semiconductor members, coating compositions, heat insulating resin compositions, light diffusing resin compositions, and light diffusing films.

Claims

1. Hollow resin particles having a shell portion and one hollow portion surrounded by the shell portion, wherein the shell portion comprises an aromatic polymer (P1) and a non-crosslinkable polymer (P2), and the aromatic polymer (P1) is obtained by the reaction of a monomer component (M) comprising an aromatic monofunctional monomer (a) and an aromatic crosslinkable monomer (b), the hollow percentage being 20% ​​to 45%, and the remaining hollow percentage after a dispersion test being 85% or more.

2. The hollow resin particles according to claim 1, wherein the monomer component (M) comprises at least one selected from the group consisting of a hydrophilic monofunctional monomer (c) and a phosphate ester-based monomer (d).

3. The hollow resin particles according to claim 1, having a volume average particle diameter of 2.0 μm to 15.0 μm.

4. The hollow resin particles according to claim 1, wherein the aromatic monofunctional monomer (a) is at least one selected from the group consisting of styrene and ethylvinylbenzene.

5. The hollow resin particle according to claim 1, wherein the aromatic crosslinkable monomer (b) is divinylbenzene.

6. The hollow resin particles according to claim 2, wherein the hydrophilic monofunctional monomer (c) is represented by general formula (1) or general formula (2). In general formula (1), R 1 represents H or CH3, R 2 represents H, an alkyl group, or a phenyl group, and R 3 represents an alkanediyl group having 2 to 18 carbon atoms, and m is R 3 the average number of moles of oxyalkylene groups represented by —O is 1 to 100, and m R 3 are independent of each other. In general formula (2), R 4 represents H or CH3, R 5 represents an alkanediyl group having 1 to 10 carbon atoms or an alkenediyl group having 2 to 10 carbon atoms, R 6 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 5 , X, R 6 are independent of each other.

7. The hollow resin particles according to claim 1, wherein the content of the aromatic crosslinkable monomer (b) is 10% by weight to 60% by weight relative to the total amount of the aromatic monofunctional monomer (a) and the aromatic crosslinkable monomer (b).

8. The hollow resin particles according to claim 2, wherein the content of the hydrophilic monofunctional monomer (c) is 0.1% by weight to 5.0% by weight relative to the total amount of the aromatic monofunctional monomer (a), the aromatic crosslinkable monomer (b), the hydrophilic monofunctional monomer (c), and the phosphate ester monomer (d).

9. The hollow resin particles according to claim 1, wherein the non-crosslinkable polymer (P2) is at least one selected from the group consisting of olefin-based polymers and styrene-based polymers.

10. The hollow resin particle according to claim 1, wherein the content of the aromatic polymer (P1) in the shell portion is 60% by weight to 99% by weight.

11. The hollow resin particle according to claim 1, wherein the content of the non-crosslinkable polymer (P2) in the shell portion is 1% by weight to 40% by weight.

12. The hollow resin particles according to any one of claims 1 to 11, which are used in a resin composition for semiconductor members.

13. A resin composition for semiconductor members, comprising the hollow resin particles according to any one of claims 1 to 11.

14. The resin composition for semiconductor members according to claim 13, which is used as an encapsulant for semiconductor chips.

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