JPWO2018230470A1 - Resin particles, conductive particles, conductive material, adhesive, connection structure, and liquid crystal display element - Google Patents

Abstract

Provided are resin particles capable of effectively suppressing the occurrence of springback and effectively suppressing the occurrence of floating or peeling. The resin particles according to the present invention have one polymerizable functional group and a first polymerizable compound having a cyclic organic group, and a second polymerizable functional group having two or more polymerizable functional groups and a cyclic organic group. And a weight ratio of the content of the structure derived from the first polymerizable compound to the content of the structure derived from the second polymerizable compound is 7 or more. When the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the particle size of the heated resin particles to the particle size of the resin particles before heating is 0.9 or less.

Description

  The present invention relates to resin particles formed from a resin. The present invention also relates to a conductive particle, a conductive material, an adhesive, a connection structure, and a liquid crystal display element using the above resin particles.

  Anisotropic conductive materials such as anisotropic conductive pastes and films are widely known. In the anisotropic conductive material, conductive particles are dispersed in a binder.

  The anisotropic conductive material is used for electrically connecting electrodes of various members to be connected such as a flexible printed circuit (FPC), a glass substrate, a glass epoxy substrate, and a semiconductor chip to obtain a connection structure. ing. In addition, conductive particles having resin particles and a conductive part disposed on the surface of the resin particles may be used as the conductive particles.

  Further, the liquid crystal display element is configured such that liquid crystal is arranged between two glass substrates. In the liquid crystal display device, a spacer is used as a gap control material in order to keep the gap (gap) between two glass substrates uniform and constant. Resin particles are generally used as the spacer.

  As an example of the conductive particles, Patent Literature 1 below discloses conductive particles having polymer particles and a conductive layer covering the surface of the polymer particles. The polymer particles may include at least one of a bifunctional (meth) acrylate monomer, a trifunctional (meth) acrylate monomer, and a tetrafunctional (meth) acrylate monomer, and a monofunctional (meth) acrylate. (Meth) acrylate monomer is copolymerized. The bifunctional (meth) acrylate monomer is 1,10-decanediol di (meth) acrylate. In the case where the polyfunctional (meth) acrylate contains the bifunctional (meth) acrylate monomer, the copolymerization component is based on 100 parts by weight of the bifunctional (meth) acrylate monomer and has the single-tube capability. (Meth) acrylate monomer is contained in a range of 10 parts by weight to 400 parts by weight. When the polyfunctional (meth) acrylate includes the tetrafunctional (meth) acrylate monomer, the copolymer component includes the tetrafunctional (meth) acrylate monomer and the single-tubular (meth) acrylate monomer. And the above-mentioned (tubular) (meth) acrylate monomer is contained in an amount of 80% by weight or less based on a total of 100% by weight. The compression deformation recovery rate of the polymer particles is 70% or more. The volume expansion coefficient of the polymer particles is 1.3 or less.

As an example of the conductive particles or the resin particles used for the spacer, Patent Document 2 below discloses highly restorable resin particles composed of a crosslinked (meth) acrylate-based resin. The average particle diameter of the high restoring resin particles is 1 μm to 100 μm. The restoration ratio of the high restoring resin particles is 22% or more. 30% compressive strength of the high resilience resin particles ^{is 1.5kgf / mm 2 ~5.0kgf / mm 2} .

WO2010 / 013668A1 WO2016 / 039357A1

  When conventional resin particles are used as conductive particles or spacers, the compressed resin particles tend to return to their original shape, and a phenomenon called springback may occur. When springback occurs in the resin particles used as the conductive particles, the contact area between the conductive particles and the electrode decreases, and the conduction reliability may decrease. Further, when springback occurs in the resin particles used as the spacer, the spacer and the member for the liquid crystal display element or the like do not sufficiently contact, and the gap control effect may not be sufficiently obtained.

  In addition, a conductive material containing conductive particles and a binder, or an adhesive containing a spacer and a binder may be exposed to a heating environment during use, and the binder may cure and shrink. Conventional resin particles do not sufficiently shrink when heated, and may not be able to follow the curing shrinkage of the binder. As a result, floating or peeling may occur between the conductive material and the electrode or between the adhesive and the liquid crystal display element member or the like.

  An object of the present invention is to provide resin particles capable of effectively suppressing the occurrence of springback and effectively suppressing the occurrence of floating or peeling. Another object of the present invention is to provide a conductive particle, a conductive material, an adhesive, a connection structure, and a liquid crystal display element using the above resin particles.

  According to a wide aspect of the present invention, a first polymerizable compound having one polymerizable functional group and having a cyclic organic group, and having two or more polymerizable functional groups and having a cyclic organic group A weight ratio of the content of the structure derived from the first polymerizable compound to the content of the structure derived from the second polymerizable compound, which is a polymer with the second polymerizable compound, is 7 or more. In addition, when the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the particle size of the resin particles after heating to the particle size of the resin particles before heating is 0.9 or less.

  In a specific aspect of the resin particles according to the present invention, the compression recovery rate when subjected to 60% compression deformation is 10% or less.

In a specific aspect of the resin particles according to the present invention, the 10% K value is 3000 N / mm ² or less.

In a specific aspect of the resin particles according to the present invention, the 30% K value is 1500 N / mm ² or less.

  In a specific aspect of the resin particles according to the present invention, when the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the 30% K value of the resin particles after heating to the 30% K value of the resin particles before heating is increased. , 0.8 or more and 1.5 or less.

  In a specific aspect of the resin particles according to the present invention, the cyclic organic group in the first polymerizable compound and the cyclic organic group in the second polymerizable compound are each a hydrocarbon group.

  In a specific aspect of the resin particles according to the present invention, the cyclic organic group in the first polymerizable compound is a phenylene group, a cyclohexyl group, or an isobornyl group.

  In a specific aspect of the resin particles according to the present invention, the cyclic organic group in the second polymerizable compound is a phenylene group, a cyclohexyl group, or an isobornyl group.

  In a specific aspect of the resin particles according to the present invention, the resin particles include an acid phosphate compound.

  In a specific aspect of the resin particle according to the present invention, the resin particle is used as a spacer or a conductive part is formed on a surface, and is used to obtain a conductive particle having the conductive part.

  According to a broad aspect of the present invention, there is provided a conductive particle including the above-described resin particle and a conductive portion disposed on a surface of the resin particle.

  According to a wide aspect of the present invention, a conductive material including conductive particles and a binder, wherein the conductive particles include the resin particles described above and a conductive portion disposed on the surface of the resin particles, Provided.

  According to a broad aspect of the present invention, there is provided an adhesive including the resin particles described above and a binder.

  According to a broad aspect of the present invention, a first connection target member having a first electrode on a surface, a second connection target member having a second electrode on a surface, the first connection target member, A connection portion that connects the second connection target member, wherein the material of the connection portion includes the resin particles described above, and the first electrode and the second electrode are connected to the connection portion. A connection structure is provided that is electrically connected by the connection structure.

  According to a wide aspect of the present invention, a first liquid crystal display element member, a second liquid crystal display element member, and a first liquid crystal display element member and a second liquid crystal display element member A liquid crystal display element is provided, comprising: a spacer disposed therebetween, wherein the spacer is the resin particles described above.

  The resin particles according to the present invention have one polymerizable functional group and a first polymerizable compound having a cyclic organic group, and a second polymerizable compound having two or more polymerizable functional groups and a cyclic organic group. 2 is a polymer with the polymerizable compound. In the resin particles according to the present invention, the weight ratio of the content of the structure derived from the first polymerizable compound to the content of the structure derived from the second polymerizable compound is 7 or more. In the resin particles according to the present invention, when the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the particle diameter of the heated resin particles to the particle diameter of the resin particles before heating is 0.9 or less. Since the resin particles according to the present invention have the above-described configuration, the occurrence of springback can be effectively suppressed, and the occurrence of floating or peeling can be effectively suppressed.

FIG. 1 is a sectional view showing the conductive particles according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view illustrating the conductive particles according to the second embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating a conductive particle according to the third embodiment of the present invention. FIG. 4 is a cross-sectional view illustrating an example of a connection structure using the conductive particles according to the first embodiment of the present invention. FIG. 5 is a cross-sectional view illustrating an example of a connection structure using the resin particles according to the present invention. FIG. 6 is a cross-sectional view showing one example of a liquid crystal display device using the resin particles according to the present invention as a spacer for a liquid crystal display device.

  Hereinafter, the present invention will be described in detail.

(Resin particles)
The resin particles according to the present invention have one polymerizable functional group and a first polymerizable compound having a cyclic organic group, and a second polymerizable compound having two or more polymerizable functional groups and a cyclic organic group. 2 is a polymer with the polymerizable compound. In the resin particles according to the present invention, the weight ratio of the content of the structure derived from the first polymerizable compound (WM) to the content of the structure derived from the second polymerizable compound (WD) (WM / WD) is 7 or more. In the resin particles according to the present invention, when the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the particle diameter of the heated resin particles to the particle diameter of the resin particles before heating (particle diameter of heated resin particles / The particle diameter of the resin particles before heating is 0.9 or less.

  In the present invention, since the above configuration is provided, the occurrence of springback can be effectively suppressed, and the occurrence of floating or peeling can be effectively suppressed.

  Since the resin particles according to the present invention are provided with the above-described configuration, the compression recovery rate is relatively low, the action of the compressed resin particles to return to the original shape is relatively hard to work, and springback occurs. Difficult to do. For example, when the resin particles according to the present invention are used as conductive particles, a decrease in the contact area between the conductive particles and the electrodes can be effectively prevented, and the conduction reliability between the electrodes can be effectively reduced. Can be enhanced. Further, when the resin particles according to the present invention are used as spacers, the spacers can be brought into sufficient contact with a member for a liquid crystal display element or the like, and the gap can be controlled with higher precision.

  In addition, a conductive material containing conductive particles and a binder, or an adhesive containing a spacer and a binder may be exposed to a heating environment at the time of use, and the binder may cure and shrink when heated. Since the resin particles according to the present invention have the above-described configuration, the resin particles contract relatively easily by heating. Since the particle size of the resin particles after heating is appropriately smaller than the particle size of the resin particles before heating, the resin particles can follow the curing shrinkage of the binder. As a result, floating or peeling can be effectively suppressed between the conductive material and the electrode or between the adhesive and the member for a liquid crystal display element.

  In the resin particles according to the present invention, the weight ratio of the content of the structure derived from the first polymerizable compound (WM) to the content of the structure derived from the second polymerizable compound (WD) (WM / WD) is 7 or more. The weight ratio (WM / WD) is preferably 9 or more, and more preferably, from the viewpoint of more effectively suppressing the occurrence of springback and the viewpoint of more effectively suppressing the occurrence of floating or peeling. It is 13 or more, preferably 20 or less, more preferably 17 or less.

  Examples of a method for obtaining the content (WM) of the structure derived from the first polymerizable compound and the content (WD) of the structure derived from the second polymerizable compound include the following methods. From the compounding amounts of the first and second polymerizable compounds used when obtaining the polymer and the remaining amount of the first and second polymerizable compounds after polymerization, the polymerized first and second polymerizable compounds The amount is determined and calculated from the amount of the polymerized first and second polymerizable compounds.

  The method for determining the content (WM) of the structure derived from the first polymerizable compound and the content (WD) of the structure derived from the second polymerizable compound from the resin particles is as follows. No. The amount of the functional group in each of the resin particles of the first and second polymerizable compounds used in obtaining the polymer, and the respective resins of the first and second polymerizable compounds used in obtaining the polymer It is calculated from the amount of the group reacted with the functional group in the particles.

  In the resin particles according to the present invention, when the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the particle diameter of the heated resin particles to the particle diameter of the resin particles before heating (particle diameter of heated resin particles / The particle diameter of the resin particles before heating is 0.9 or less. From the viewpoint of more effectively suppressing the occurrence of floating or peeling, the ratio (particle diameter of resin particles after heating / particle diameter of resin particles before heating) is preferably 0.4 or more, more preferably It is 0.6 or more, preferably 0.85 or less, more preferably 0.8 or less.

  The particle size of the resin particles (the particle size of the resin particles before heating) can be appropriately set depending on the application. The particle size of the resin particles is preferably 0.5 μm or more, more preferably 1 μm or more, preferably 500 μm or less, more preferably 300 μm or less, even more preferably 150 μm or less, even more preferably 100 μm or less, particularly preferably It is 50 μm or less. When the particle size of the resin particles is equal to or greater than the lower limit and equal to or less than the upper limit, the occurrence of springback can be more effectively suppressed, and the occurrence of floating or peeling can be more effectively suppressed. be able to. When the particle diameter of the resin particles is 0.5 μm or more and 500 μm or less, the resin particles can be suitably used for conductive particles. When the particle diameter of the resin particles is 0.5 μm or more and 500 μm or less, the resin particles can be suitably used for a spacer.

  The particle diameter of the resin particles (the particle diameter of the resin particles before heating and the particle diameter of the resin particles after heating) indicates the diameter when the resin particles are truly spherical, and when the resin particles are not truly spherical. Indicates the maximum diameter.

  The particle size of the resin particles (the particle size of the resin particles before heating and the particle size of the resin particles after heating) is preferably an average particle size, and more preferably a number average particle size. The particle size of the resin particles is determined using a particle size distribution measuring device or the like. For example, a particle size distribution measuring apparatus using principles such as laser scattered light, electric resistance change, and image analysis after imaging can be used. Specifically, as a method for measuring the particle size of the resin particles, for example, using a particle size distribution measuring device (“Multisizer 4” manufactured by Beckman Coulter, Inc.), the particle size of about 100,000 resin particles is measured, and the average value is measured. Is calculated. The particle diameter of the resin particles is preferably obtained by observing 50 arbitrary resin particles with an electron microscope or an optical microscope and calculating an average value. When measuring the particle size of the resin particles in the conductive particles, the measurement can be performed, for example, as follows.

  A conductive particle inspection embedding resin is prepared by adding and dispersing the conductive particles to “Technobit 4000” manufactured by Kulzer so that the content of the conductive particles becomes 30% by weight. The cross section of the conductive particles is cut out using an ion milling apparatus (“IM4000” manufactured by Hitachi High-Technologies Corporation) so as to pass near the center of the conductive particles dispersed in the resin for inspection. Then, using a field emission scanning electron microscope (FE-SEM), the image magnification is set to 25,000 times, 50 conductive particles are randomly selected, and the resin particles of each conductive particle are observed. . The particle diameter of the resin particles in each conductive particle is measured, and arithmetically averaged to obtain the particle diameter of the resin particles.

  From the viewpoint of more effectively suppressing the occurrence of springback and the more effectively suppressing the occurrence of floating or peeling, the coefficient of variation (CV value) of the particle diameter of the resin particles is preferably 0. It is at least 0.5%, more preferably at least 1%, preferably at most 10%, more preferably at most 7%. When the variation coefficient of the particle diameter of the resin particles is equal to or greater than the lower limit and equal to or less than the upper limit, the resin particles can be suitably used for spacers and conductive particles. However, the coefficient of variation of the particle size of the resin particles may be less than 0.5%.

  The variation coefficient (CV value) can be measured as follows.

CV value (%) = (ρ / Dn) × 100
ρ: Standard deviation of particle diameter of resin particles Dn: Average value of particle diameter of resin particles

  The shape of the resin particles is not particularly limited. The shape of the resin particles may be spherical or may be other than spherical, such as flat.

10% K value of the resin particles is preferably 1000 N / mm ² or more, more preferably 1500 N / mm ² or more, preferably 3000N / mm ² or less, more preferably 2750N / mm ² or less, more preferably 2500N / it mm ² or less. When the 10% K value of the resin particles is equal to or more than the lower limit and equal to or less than the upper limit, the occurrence of springback can be more effectively suppressed, and the occurrence of floating or peeling can be more effectively prevented. Can be suppressed.

The 30% K value of the resin particles is preferably 300 N / mm ² or more, more preferably 500 N / mm ² or more, preferably 1500 N / mm ² or less, more preferably 1200 N / mm ² or less, and even more preferably 1000 N / mm ² or less. it mm ² or less. When the 30% K value of the resin particles is equal to or greater than the lower limit and equal to or less than the upper limit, generation of springback can be more effectively suppressed, and occurrence of floating or peeling can be more effectively reduced. Can be suppressed.

  When the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the 30% K value of the resin particles after heating to the 30% K value of the resin particles before heating (30% K value of the resin particles after heating / before heating) (30% K value of the resin particles) is preferably 0.8 or more, more preferably 1.15 or more, and still more preferably 1.2 or more. When the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the 30% K value of the resin particles after heating to the 30% K value of the resin particles before heating (30% K value of the resin particles after heating / before heating) (30% K value of the resin particles) is preferably 1.5 or less, more preferably 1.45 or less, and still more preferably 1.4 or less. When the ratio (30% K value of resin particles after heating / 30% K value of resin particles before heating) is not less than the lower limit and not more than the upper limit, generation of springback is more effectively suppressed. And the occurrence of floating or peeling can be more effectively suppressed.

  The 10% K value and the 30% K value (compression elastic modulus when the resin particles are compressed by 10% and compression elastic modulus when the resin particles are compressed by 30%) of the resin particles can be measured as follows.

  Using a micro-compression tester, one resin particle is compressed under the conditions of a compression speed of 0.3 mN / sec and a maximum test load of 20 mN at 25 ° C. on a smooth indenter end face of a cylinder (diameter: 100 μm, made of diamond). . At this time, the load value (N) and the compression displacement (mm) are measured. From the obtained measured values, a 10% K value or a 30% K value at 25 ° C. can be determined by the following equation. As the micro compression tester, for example, "Micro compression tester MCT-W200" manufactured by Shimadzu Corporation and "Fischer Scope H-100" manufactured by Fischer are used. The 10% K value or 30% K value of the resin particles is preferably calculated by arithmetically averaging the 10% K value or 30% K value of the arbitrarily selected 50 resin particles.

10% K value or 30% K value (N / mm ² ) = (3/2 ^1/2 ) ・^FS -3 ^{/ 2}・ R ^{１ ／}
F: Load value when resin particles undergo 10% compression deformation (N) or load value when 30% compression deformation occurs (N)
S: Compressive displacement (mm) when resin particles undergo 10% compressive deformation or compressive displacement (mm) when resin particles undergo 30% compressive deformation
R: radius of resin particles (mm)

  The K value universally and quantitatively represents the hardness of the resin particles. By using the K value, the hardness of the resin particles can be quantitatively and uniquely expressed.

  From the viewpoint of more effectively suppressing the occurrence of springback, and the viewpoint of more effectively suppressing the occurrence of floating or peeling, the compression recovery rate when the resin particles are subjected to 60% compression deformation is preferably It is at least 2%, more preferably at least 4%, preferably at most 10%, more preferably at most 9.5%, even more preferably at most 9%.

  The compression recovery rate when the resin particles are compressed and deformed by 60% can be measured as follows.

  Spray resin particles on the sample stage. Using a micro-compression tester, one dispersed resin particle is subjected to 60% compression deformation of the resin particle toward the center of the resin particle at 25 ° C. at the end face of a cylindrical (diameter: 100 μm, made of diamond) smooth indenter. Apply load (reversal load value) up to. Thereafter, unloading is performed up to the origin load value (0.40 mN). The load-compression displacement during this time is measured, and the compression recovery rate at the time of 60% compression deformation at 25 ° C. can be obtained from the following equation. The load speed is 0.33 mN / sec. As the micro compression tester, for example, "Micro compression tester MCT-W200" manufactured by Shimadzu Corporation and "Fischer Scope H-100" manufactured by Fischer are used.

Compression recovery rate (%) = [L2 / L1] × 100
L1: Compressive displacement from load value for origin to reverse load value when applying load L2: Unload displacement from reverse load value to load value for origin when releasing load

  The use of the resin particles is not particularly limited. The resin particles are suitably used for various applications. The resin particles are preferably used as spacers or used to obtain conductive particles having a conductive portion. In the conductive particle, the conductive portion is formed on a surface of the resin particle. The resin particles are preferably used as a spacer. The resin particles are preferably used to obtain conductive particles having a conductive part. Examples of the method of using the spacer include a spacer for a liquid crystal display element, a spacer for gap control, a spacer for stress relaxation, and the like. The gap control spacer is used for gap control of a laminated chip for securing stand-off height and flatness, and gap control of an optical component for securing smoothness of a glass surface and thickness of an adhesive layer. Can be used. The stress relaxation spacer can be used for stress relaxation of a sensor chip and the like, and stress relaxation of a connection portion connecting two connection target members.

  The resin particles are preferably used as a spacer for a liquid crystal display element, and are preferably used as a peripheral sealant for a liquid crystal display element. In the peripheral sealant for a liquid crystal display element, the resin particles preferably function as spacers. Since the resin particles have good compressive deformation characteristics, the resin particles are arranged between substrates by using the resin particles as spacers, or a conductive portion is formed on the surface to electrically connect the electrodes by using the conductive particles as conductive particles. In this case, spacers or conductive particles are efficiently disposed between the substrates or between the electrodes. Further, since the resin particles can suppress damage to the liquid crystal display element member and the like, poor connection is caused in the liquid crystal display element using the liquid crystal display element spacer and the connection structure using the conductive particles. In addition, display defects are less likely to occur.

  Further, the resin particles are suitably used as an inorganic filler, a toner additive, a shock absorber or a vibration absorber. For example, the above resin particles can be used as a substitute for rubber or a spring.

(Other details of resin particles)
The resin particles according to the present invention have one polymerizable functional group and a first polymerizable compound having a cyclic organic group, and a second polymerizable compound having two or more polymerizable functional groups and a cyclic organic group. 2 is a polymer with the polymerizable compound. The resin particles are preferably obtained by polymerizing the first polymerizable compound and the second polymerizable compound.

  From the viewpoint of more effectively suppressing the occurrence of springback, and from the viewpoint of more effectively suppressing the occurrence of floating or peeling, in the resin particles, the central portion of the resin particles and the surface portion of the resin particles. It is preferable to be composed of the same polymer. The compounding ratio of the polymerizable compound at the center of the resin particles and the compounding ratio of the polymerizable compound at the surface of the resin particles may be the same or different. The composition ratio of the components at the center of the resin particles and the composition ratio of the components at the surface of the resin particles may be the same or different.

  In the resin particles, it is preferable that the center of the resin particles is formed of a material for forming a center portion, and the surface portion of the resin particles is formed of a material for forming a surface portion. From the viewpoint of more effectively suppressing the occurrence of springback, and the viewpoint of more effectively suppressing the occurrence of floating or peeling, in the resin particles, the components of the central portion forming material and the surface portion forming material The components are preferably the same. In the resin particles, the component ratio of the central portion forming material and the component ratio of the surface portion forming material may be the same or different. In addition, it is preferable that the resin particles have a region including both the center portion forming material and the surface portion forming material. In the resin particles, it is preferable that the resin particles have a region in the center portion that includes the center portion forming material and does not include the surface portion forming material or includes the surface portion forming material in less than 25%. In the resin particles, it is preferable that the resin particles have a region on the surface portion that includes the surface portion forming material and does not include the center portion forming material or includes the center portion forming material in less than 25%.

  The resin particles are preferably not core-shell particles having a core and a shell disposed on the surface of the core, and preferably do not have an interface between the core and the shell in the resin particles. The resin particles preferably have no interface in the resin particles, and more preferably do not have an interface where different surfaces are in contact with each other. The resin particles preferably do not have a discontinuous portion where a surface is present, and preferably do not have a discontinuous portion where a structural surface is present.

  In the resin particles according to the present invention, the first polymerizable compound has one polymerizable functional group (first polymerizable functional group). The polymerizable functional group (first polymerizable functional group) is not particularly limited, and includes, for example, a vinyl group, an acryloyl group, and a methacryloyl group. Examples of the first polymerizable compound include styrene, phenyl methacrylate, phenyl acrylate, cyclohexyl methacrylate, cyclohexyl acrylate, isobornyl methacrylate, and isobornyl acrylate. As the first polymerizable compound, only one kind may be used, or two or more kinds may be used in combination.

  In the resin particles according to the present invention, the second polymerizable compound has two or more polymerizable functional groups (second polymerizable functional groups). The polymerizable functional group (second polymerizable functional group) is not particularly limited, and includes, for example, a vinyl group, an acryloyl group, and a methacryloyl group. Examples of the second polymerizable compound include divinylbenzene, divinylnaphthalene, divinylcyclohexane, and trivinylcyclohexane. As the second polymerizable compound, only one kind may be used, or two or more kinds may be used in combination.

  The resin particles are preferably in a weight ratio of the first polymerizable compound and the second polymerizable compound (weight of the first polymerizable compound / weight of the second polymerizable compound) of 7 or more; More preferably, it is obtained by polymerization at 9 or more, more preferably 13 or more, preferably 20 or less, more preferably 18.5 or less, and still more preferably 17 or less. The resin particles are preferably obtained by polymerizing the first polymerizable compound and the second polymerizable compound at a weight ratio of 7 or more, more preferably 9 or more, and more preferably 13 or more. It is more preferable to obtain the above by polymerization. The resin particles are preferably obtained by polymerizing the first polymerizable compound and the second polymerizable compound at a weight ratio of 20 or less, more preferably 18.5 or less. , 17 or less. The resin particles are obtained by polymerizing the first polymerizable compound and the second polymerizable compound at a weight ratio within the above-mentioned preferred range, thereby suppressing the occurrence of springback more effectively. And the occurrence of floating or peeling can be more effectively suppressed.

  The resin particles according to the present invention preferably contain two or more types of cyclic organic groups. In the resin particles according to the present invention, the first polymerizable compound has a cyclic organic group (first cyclic organic group). The first polymerizable compound has one or more cyclic organic groups. In the resin particles according to the present invention, the second polymerizable compound has a cyclic organic group (second cyclic organic group). The second polymerizable compound has one or more cyclic organic groups. In the resin particles according to the present invention, the cyclic organic group (first cyclic organic group) in the first polymerizable compound and the cyclic organic group (second cyclic organic group) in the second polymerizable compound are the same. And may be different. It is preferable that the cyclic organic group (first cyclic organic group) in the first polymerizable compound and the cyclic organic group (second cyclic organic group) in the second polymerizable compound are different.

  From the viewpoint of suppressing the occurrence of springback more effectively and the viewpoint of suppressing the occurrence of floating or peeling more effectively, the cyclic organic group (the first cyclic organic group) in the first polymerizable compound is preferred. ) And the cyclic organic group (second cyclic organic group) in the second polymerizable compound are each preferably a hydrocarbon group.

  Examples of the hydrocarbon group include a phenyl group, a phenylene group, a naphthyl group, a naphthylene group, a cyclopropyl group, a cyclohexyl group, an isobornyl group, and a dicyclopentanyl group.

  From the viewpoint of more effectively suppressing the occurrence of springback, and the viewpoint of more effectively suppressing the occurrence of lifting or peeling, the resin particles according to the present invention are preferably phenylene, cyclohexyl, or isobornyl groups. It is preferable to have two or more cyclic organic groups.

  From the viewpoint of suppressing the occurrence of springback more effectively and the viewpoint of suppressing the occurrence of floating or peeling more effectively, the cyclic organic group (the first cyclic organic group) in the first polymerizable compound is preferred. ) Is preferably a phenylene group, a cyclohexyl group or an isobornyl group.

  From the viewpoint of suppressing the occurrence of springback more effectively and the viewpoint of suppressing the occurrence of floating or peeling more effectively, the cyclic organic group (second cyclic organic group) in the second polymerizable compound is preferred. ) Is preferably a phenylene group, a cyclohexyl group or an isobornyl group.

  When the resin particles are used as conductive particles, the resin particles preferably contain an acid phosphate compound from the viewpoint of more effectively improving the adhesion between the resin particles and the plating. The resin particles preferably have a phosphoric acid structure derived from an acid phosphate compound on the surface. When the resin particles have the phosphoric acid structure on the surface, the adhesion to plating can be more effectively increased. Further, since the resin particles have the phosphoric acid structure on the surface, even if the resin particles shrink by heating, plating cracks can be more effectively suppressed. For example, in a conductive material containing a binder and a conductive particle produced by electroless plating resin particles containing an acid phosphate compound, the conductive material is heated at the time of connection between the electrodes, or the conductive material is exposed to a heating environment. Even if it does, plating cracks can be more effectively suppressed, and the connection reliability between the electrodes can be more effectively increased. When the resin particles are used to obtain conductive particles, the resin particles preferably include an acid phosphate compound. When the resin particles are used to obtain conductive particles, the resin particles preferably have a phosphoric acid structure derived from an acid phosphate compound on the surface. The acid phosphate compound is preferably an acidic phosphate compound.

  Examples of the acid phosphate compound include ethyl acid phosphate, butyl acid phosphate, butoxyethyl acid phosphate, 2-ethylhexyl acid phosphate, isotridecyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate, ethylene glycol acid phosphate, and 2-hydroxy acid. Ethyl methacrylic acid phosphate, dibutyl acid phosphate, bis (2-ethylhexyl) acid phosphate and the like can be mentioned. One of the above acid phosphate compounds may be used alone, or two or more thereof may be used in combination.

  From the viewpoint of more effectively increasing the adhesion between the resin particles and the plating, the content of the acid phosphate compound in 100% by weight of the resin particles is preferably 1% by weight or more, more preferably 5% by weight or more. , Preferably 20% by weight or less, more preferably 15% by weight or less.

(Conductive particles)
The conductive particles according to the present invention include the above-described resin particles and a conductive portion disposed on the surface of the resin particles.

  FIG. 1 is a sectional view showing the conductive particles according to the first embodiment of the present invention.

  The conductive particles 1 shown in FIG. 1 have resin particles 11 and conductive portions 2 arranged on the surface of the resin particles 11. The conductive part 2 is in contact with the surface of the resin particle 11. The conductive portion 2 covers the surface of the resin particle 11. The conductive particles 1 are coated particles in which the surfaces of the resin particles 11 are coated with the conductive portions 2. In the conductive particles 1, the conductive part 2 is a single-layer conductive part (conductive layer).

  FIG. 2 is a cross-sectional view illustrating the conductive particles according to the second embodiment of the present invention.

  The conductive particles 21 shown in FIG. 2 have the resin particles 11 and the conductive portions 22 arranged on the surface of the resin particles 11. The conductive part 22 has a first conductive part 22A on the resin particle 11 side and a second conductive part 22B on the side opposite to the resin particle 11 side as a whole.

  The only difference between the conductive particles 1 shown in FIG. 1 and the conductive particles 21 shown in FIG. That is, in the conductive particles 1, a conductive portion having a one-layer structure is formed, whereas in the conductive particles 21, a first conductive portion 22A and a second conductive portion 22B having a two-layer structure are formed. I have. The first conductive part 22A and the second conductive part 22B may be formed as different conductive parts, or may be formed as the same conductive part.

  The first conductive portion 22 </ b> A is arranged on the surface of the resin particle 11. The first conductive portion 22A is arranged between the resin particle 11 and the second conductive portion 22B. First conductive portion 22A is in contact with resin particles 11. The second conductive part 22B is in contact with the first conductive part 22A. The first conductive portion 22A is disposed on the surface of the resin particle 11, and the second conductive portion 22B is disposed on the surface of the first conductive portion 22A.

  FIG. 3 is a cross-sectional view illustrating a conductive particle according to the third embodiment of the present invention.

  The conductive particles 31 shown in FIG. 3 include the resin particles 11, conductive portions 32, a plurality of core materials 33, and a plurality of insulating materials 34. The conductive part 32 is arranged on the surface of the resin particle 11. The plurality of core substances 33 are arranged on the surface of the resin particles 11. The conductive part 32 is disposed on the surface of the resin particle 11 so as to cover the resin particle 11 and the plurality of core substances 33. In the conductive particles 31, the conductive part 32 is a single-layer conductive part (conductive layer).

  The conductive particles 31 have a plurality of protrusions 31a on the outer surface. In the conductive particles 31, the conductive portion 32 has a plurality of protrusions 32a on the outer surface. The plurality of core substances 33 raise the outer surface of the conductive part 32. The projections 31a and 32a are formed by the outer surface of the conductive portion 32 being raised by the plurality of core substances 33. The plurality of core substances 33 are embedded in the conductive part 32. The core substance 33 is disposed inside the projections 31a and 32a. In the conductive particles 31, a plurality of core substances 33 are used to form the projections 31a and 32a. In the conductive particles, a plurality of the core materials may not be used to form the protrusions. The conductive particles may not include a plurality of the core materials.

  The conductive particles 31 have an insulating substance disposed on the outer surface of the conductive part 32. At least a part of the outer surface of the conductive portion 32 is covered with an insulating material 34. The insulating substance 34 is formed of a material having an insulating property, and is an insulating particle. Thus, the conductive particles according to the present invention may have an insulating substance disposed on the outer surface of the conductive part. However, the conductive particles do not necessarily have to have an insulating substance. The conductive particles need not include a plurality of insulating substances.

Conductive part:
The metal for forming the conductive portion is not particularly limited. Examples of the metal include gold, silver, palladium, copper, platinum, zinc, iron, tin, lead, aluminum, cobalt, indium, nickel, chromium, titanium, antimony, bismuth, thallium, germanium, cadmium, silicon, and tungsten. , Molybdenum and alloys thereof. Examples of the metal include tin-doped indium oxide (ITO) and solder. An alloy containing tin, nickel, palladium, copper or gold is preferable, and nickel or palladium is preferable because the connection resistance between the electrodes can be further reduced.

  Further, since the conduction reliability can be effectively improved, it is preferable that the conductive portion and the outer surface portion of the conductive portion contain nickel. The content of nickel in 100% by weight of the conductive portion containing nickel is preferably 10% by weight or more, more preferably 50% by weight or more, still more preferably 60% by weight or more, further preferably 70% by weight or more, and particularly preferably. Is 90% by weight or more. The content of nickel in the conductive portion containing 100% by weight of nickel may be 97% by weight or more, 97.5% by weight or more, or 98% by weight or more.

  Note that a hydroxyl group is often present on the surface of the conductive portion due to oxidation. Generally, a hydroxyl group is present on the surface of a conductive portion formed of nickel due to oxidation. An insulating substance can be arranged on the surface of the conductive portion having such a hydroxyl group (the surface of the conductive particles) via a chemical bond.

  Like the conductive particles 1 and 31, the conductive portion may be formed by one layer. Like the conductive particles 21, the conductive portion may be formed by a plurality of layers. That is, the conductive portion may have a laminated structure of two or more layers. When the conductive portion is formed of a plurality of layers, the outermost layer is preferably a gold layer, a nickel layer, a palladium layer, a copper layer, or an alloy layer containing tin and silver, and is preferably a gold layer. Is more preferred. When the outermost layer is one of these preferred conductive portions, the connection resistance between the electrodes can be reduced even more effectively. When the outermost layer is a gold layer, the corrosion resistance can be more effectively increased.

  The method for forming the conductive portion on the surface of the resin particles is not particularly limited. As a method of forming the conductive portion, for example, a method by electroless plating, a method by electroplating, a method by physical vapor deposition, and a method of coating the surface of resin particles with a metal powder or a paste containing a metal powder and a binder And the like. The method using electroless plating is preferable because the formation of the conductive portion is simple. Examples of the method by physical vapor deposition include methods such as vacuum vapor deposition, ion plating, and ion sputtering.

  The particle size of the conductive particles is preferably 0.5 μm or more, more preferably 1.0 μm or more, preferably 500 μm or less, more preferably 450 μm or less, even more preferably 100 μm or less, even more preferably 50 μm or less, Particularly preferably, it is 20 μm or less. When the particle size of the conductive particles is equal to or greater than the lower limit and equal to or less than the upper limit, the contact area between the conductive particles and the electrode is sufficiently large when the electrodes are connected using the conductive particles, and Aggregated conductive particles are less likely to be formed when forming the conductive portion. In addition, the distance between the electrodes connected via the conductive particles does not become too large, and the conductive portion does not easily peel off from the surface of the resin particles. When the particle size of the conductive particles is equal to or larger than the lower limit and equal to or smaller than the upper limit, the conductive particles can be suitably used for a conductive material.

  The particle diameter of the conductive particles indicates a diameter when the conductive particles are truly spherical, and indicates a maximum diameter when the conductive particles are not truly spherical.

  The particle size of the conductive particles is preferably an average particle size, and more preferably a number average particle size. The particle diameter of the conductive particles, for example, by observing 50 arbitrary conductive particles with an electron microscope or an optical microscope, calculating the average value, and a plurality of times measurement results by a laser diffraction particle size distribution analyzer Is calculated by calculating the average value of.

  The thickness of the conductive portion is preferably 0.005 μm or more, more preferably 0.01 μm or more, preferably 10 μm or less, more preferably 1 μm or less, and still more preferably 0.3 μm or less. When the thickness of the conductive portion is not less than the lower limit and not more than the upper limit, sufficient conductivity is obtained, and the conductive particles are not too hard, and the conductive particles are sufficiently formed at the time of connection between the electrodes. Deform.

  When the conductive portion is formed of a plurality of layers, the thickness of the outermost conductive portion is preferably 0.001 μm or more, more preferably 0.01 μm or more, preferably 0.5 μm or less, more preferably Is 0.1 μm or less. When the thickness of the conductive portion of the outermost layer is not less than the lower limit and not more than the upper limit, the coating by the conductive portion of the outermost layer becomes uniform, the corrosion resistance is sufficiently high, and the connection resistance between the electrodes is sufficient. Lower. When the outermost layer is a gold layer, the cost is lower as the thickness of the gold layer is smaller.

  The thickness of the conductive portion can be measured, for example, by observing a cross section of the conductive particles using a transmission electron microscope (TEM). Regarding the thickness of the conductive portion, it is preferable to calculate the average value of the five conductive portions at an arbitrary thickness as the thickness of the conductive portion of one conductive particle, and calculate the average value of the thickness of the entire conductive portion as one. More preferably, it is calculated as the thickness of the conductive portion. In the case of a plurality of conductive particles, the thickness of the conductive portion is preferably obtained by calculating an average value of these values for 10 arbitrary conductive particles.

Core material:
The conductive particles preferably have a plurality of protrusions on the outer surface of the conductive portion. Since the conductive particles have a plurality of protrusions on the outer surface of the conductive portion, the reliability of conduction between the electrodes can be further improved. An oxide film is often formed on the surface of the electrode connected by the conductive particles. Further, an oxide film is often formed on the surface of the conductive portion of the conductive particles. By using the conductive particles having the protrusions, the conductive particles are arranged between the electrodes, and then pressed, whereby the oxide film is effectively removed by the protrusions. For this reason, an electrode and conductive particles can be more reliably contacted, and the connection resistance between electrodes can be reduced more effectively. Furthermore, when the conductive particles have an insulating material on the surface, or when the conductive particles are dispersed in a binder resin and used as a conductive material, the protrusions of the conductive particles cause the conductive particles and the electrode to be in contact with each other. The insulating material and the binder resin between them are effectively eliminated. For this reason, the conduction reliability between the electrodes can be more effectively improved.

  By embedding the core material in the conductive portion, a plurality of protrusions can be easily formed on the outer surface of the conductive portion. However, in order to form a projection on the surface of the conductive portion of the conductive particles, the core material may not be necessarily used.

  As a method of forming the projections, after attaching a core substance to the surface of the resin particles, a method of forming a conductive portion by electroless plating, and after forming a conductive portion by electroless plating on the surface of the resin particles, A method of attaching a core substance and forming a conductive portion by electroless plating is also used. As another method of forming the above-mentioned protrusion, after forming a first conductive portion on the surface of the resin particles, a core substance is disposed on the first conductive portion, and then the second conductive portion is formed. Examples of the method include a forming method, and a method of adding a core substance in the middle of forming a conductive portion (such as a first conductive portion or a second conductive portion) on the surface of resin particles. Also, in order to form projections, without using the above-mentioned core substance, after forming a conductive portion on the resin particles by electroless plating, plating is deposited on the surface of the conductive portion in the form of protrusions, and further by electroless plating. A method of forming a conductive portion or the like may be used.

  As a method of arranging the core material on the surface of the resin particles, for example, a core material is added to a dispersion of the resin particles, and the core material is accumulated on the surface of the resin particles by van der Waals force and adhered. And a method in which a core substance is added to a container containing resin particles, and the core substance is attached to the surface of the resin particles by mechanical action such as rotation of the container. Since it is easy to control the amount of the core substance to be attached, a method of accumulating and attaching the core substance to the surface of the resin particles in the dispersion is preferable.

  The material of the core substance is not particularly limited. Examples of the material of the core substance include a conductive substance and a non-conductive substance. Examples of the conductive substance include metals, oxides of metals, conductive nonmetals such as graphite, and conductive polymers. Examples of the conductive polymer include polyacetylene. Examples of the non-conductive substance include silica, alumina, barium titanate, and zirconia. Metals are preferred because conductivity can be increased and connection resistance can be effectively reduced. The core material is preferably metal particles. As the metal which is the material of the core substance, any of the metals mentioned as the metal for forming the conductive portion can be used as appropriate.

Insulating material:
It is preferable that the conductive particles include an insulating substance disposed on a surface of the conductive portion. In this case, when the conductive particles are used for connection between the electrodes, a short circuit between adjacent electrodes can be further prevented. Specifically, when a plurality of conductive particles come into contact with each other, an insulating substance is present between the plurality of electrodes, so that a short circuit between not only upper and lower electrodes but also horizontally adjacent electrodes can be prevented. When the conductive particles are pressurized by the two electrodes at the time of connection between the electrodes, the insulating substance between the conductive portion of the conductive particles and the electrode can be easily removed. When the conductive particles have a plurality of protrusions on the outer surface of the conductive portion, the insulating substance between the conductive portion of the conductive particles and the electrode can be more easily removed.

  The insulating material is preferably an insulating particle because the insulating material can be more easily removed at the time of pressure bonding between the electrodes.

  Examples of the material of the insulating material include polyolefin compounds, (meth) acrylate polymers, (meth) acrylate copolymers, block polymers, thermoplastic resins, crosslinked thermoplastic resins, thermosetting resins, and water-soluble resins. Is mentioned. As the material of the insulating substance, only one kind may be used, or two or more kinds may be used in combination.

  Examples of the polyolefin compound include polyethylene, an ethylene-vinyl acetate copolymer, and an ethylene-acrylate copolymer. Examples of the (meth) acrylate polymer include polymethyl (meth) acrylate, polydodecyl (meth) acrylate, and polystearyl (meth) acrylate. Examples of the block polymer include polystyrene, styrene-acrylate copolymer, SB-type styrene-butadiene block copolymer, SBS-type styrene-butadiene block copolymer, and hydrogenated products thereof. Examples of the thermoplastic resin include a vinyl polymer and a vinyl copolymer. Examples of the thermosetting resin include an epoxy resin, a phenol resin, and a melamine resin. Examples of the crosslinking of the thermoplastic resin include introduction of polyethylene glycol methacrylate, alkoxylated trimethylolpropane methacrylate, and alkoxylated pentaerythritol methacrylate. Examples of the water-soluble resin include polyvinyl alcohol, polyacrylic acid, polyacrylamide, polyvinylpyrrolidone, polyethylene oxide, and methyl cellulose. Further, a chain transfer agent may be used for adjusting the degree of polymerization. Examples of the chain transfer agent include thiol and carbon tetrachloride.

  Examples of a method for disposing an insulating substance on the surface of the conductive portion include a chemical method and a physical or mechanical method. Examples of the chemical method include an interfacial polymerization method, a suspension polymerization method in the presence of particles, and an emulsion polymerization method. Examples of the physical or mechanical method include spray drying, hybridization, electrostatic adhesion, spraying, dipping, and vacuum deposition. Since the insulating substance is not easily detached, a method of disposing the insulating substance on the surface of the conductive portion via a chemical bond is preferable.

  The outer surface of the conductive portion and the surface of the insulating material may be respectively coated with a compound having a reactive functional group. The outer surface of the conductive portion and the surface of the insulating material may not be directly chemically bonded, or may be indirectly chemically bonded by a compound having a reactive functional group. After introducing a carboxyl group to the outer surface of the conductive portion, the carboxyl group may be chemically bonded to a functional group on the surface of the insulating material via a polymer electrolyte such as polyethyleneimine.

(Conductive material)
The conductive material according to the present invention includes the above-described conductive particles and a binder. The conductive particles are preferably used by being dispersed in a binder, and are preferably used by being dispersed in a binder and being used as a conductive material. The conductive material is preferably an anisotropic conductive material. The conductive material is preferably used for electrical connection between electrodes. The conductive material is preferably a circuit-connecting conductive material.

  The binder is not particularly limited. As the binder, a known insulating resin is used. The binder preferably contains a thermoplastic component (thermoplastic compound) or a curable component, and more preferably contains a curable component. Examples of the curable component include a photocurable component and a thermosetting component. The photocurable component preferably contains a photocurable compound and a photopolymerization initiator. The thermosetting component preferably contains a thermosetting compound and a thermosetting agent.

  Examples of the binder include a vinyl resin, a thermoplastic resin, a curable resin, a thermoplastic block copolymer, and an elastomer. The binder may be used alone or in combination of two or more.

  Examples of the vinyl resin include a vinyl acetate resin, an acrylic resin, and a styrene resin. Examples of the thermoplastic resin include a polyolefin resin, an ethylene-vinyl acetate copolymer, and a polyamide resin. Examples of the curable resin include an epoxy resin, a urethane resin, a polyimide resin, and an unsaturated polyester resin. The curable resin may be a room temperature curable resin, a thermosetting resin, a photocurable resin, or a moisture curable resin. The curable resin may be used in combination with a curing agent. Examples of the thermoplastic block copolymer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, hydrogenated styrene-butadiene-styrene block copolymer, and styrene-isoprene. -Hydrogenated products of styrene block copolymers. Examples of the elastomer include a styrene-butadiene copolymer rubber and an acrylonitrile-styrene block copolymer rubber.

  The conductive material, in addition to the conductive particles and the binder, for example, fillers, extenders, softeners, plasticizers, polymerization catalysts, curing catalysts, colorants, antioxidants, heat stabilizers, light stabilizers And various additives such as an ultraviolet absorber, a lubricant, an antistatic agent and a flame retardant.

  A method for dispersing the conductive particles in the binder can be a conventionally known dispersion method, and is not particularly limited. As a method of dispersing the conductive particles in the binder, after adding the conductive particles in the binder, a method of kneading and dispersing with a planetary mixer or the like, the conductive particles in water or an organic solvent After uniformly dispersing the mixture using a homogenizer or the like, adding the mixture to the binder, kneading with a planetary mixer or the like, and dispersing the mixture. Further, as a method of dispersing the conductive particles in the binder, a method of diluting the binder with water or an organic solvent, and then adding the conductive particles, kneading and dispersing with a planetary mixer, and the like. Is mentioned.

  The conductive material can be used as a conductive paste and a conductive film. When the conductive material is a conductive film, a film containing no conductive particles may be laminated on a conductive film containing conductive particles. The conductive paste is preferably an anisotropic conductive paste. The conductive film is preferably an anisotropic conductive film.

  In 100% by weight of the conductive material, the content of the binder is preferably 10% by weight or more, more preferably 30% by weight or more, further preferably 50% by weight or more, particularly preferably 70% by weight or more, and preferably It is at most 99.99% by weight, more preferably at most 99.9% by weight. When the content of the binder is equal to or more than the lower limit and equal to or less than the upper limit, the conductive particles are efficiently arranged between the electrodes, and the connection reliability of the connection target member connected by the conductive material is further increased.

  In 100% by weight of the conductive material, the content of the conductive particles is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, preferably 80% by weight or less, more preferably 60% by weight. %, More preferably 40% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less. When the content of the conductive particles is equal to or greater than the lower limit and equal to or less than the upper limit, conduction reliability between the electrodes is further increased.

(adhesive)
The adhesive according to the present invention includes the resin particles described above and a binder. The resin particles are preferably used by being dispersed in a binder, and are preferably used by being dispersed in a binder and being used as an adhesive. The resin particles are preferably used as a spacer in a binder. The adhesive may not include conductive particles.

  The adhesive is used to form an adhesive layer that bonds two members to be connected. Further, the adhesive is used to control the gap of the adhesive layer with high accuracy, or to relieve the stress of the adhesive layer.

  The binder is not particularly limited. Specific examples of the binder include a binder used for the above-described conductive material. The adhesive preferably contains an epoxy resin as the binder.

  The content of the binder in 100% by weight of the adhesive is preferably 10% by weight or more, more preferably 30% by weight or more, further preferably 50% by weight or more, particularly preferably 70% by weight or more, and preferably It is at most 99.99% by weight, more preferably at most 99.9% by weight. When the content of the binder is equal to or greater than the lower limit and equal to or less than the upper limit, the adhesive force of the adhesive layer can be more effectively increased, and the resin particles exhibit the function as a spacer more effectively. can do.

  The content of the resin particles in 100% by weight of the adhesive is preferably 0.01% by weight or more, more preferably 0.1% by weight or more, preferably 80% by weight or less, more preferably 60% by weight. The content is more preferably 40% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less. When the content of the resin particles is equal to or greater than the lower limit and equal to or less than the upper limit, the resin particles can more effectively exhibit a function as a spacer.

(Connection structure)
A connection structure can be obtained by connecting the connection target members using the conductive particles or using a conductive material including the conductive particles and a binder.

  The connection structure according to the present invention includes a first connection target member having a first electrode on the surface, a second connection target member having a second electrode on the surface, the first connection target member, A connection portion connecting the second connection target member. The material of the connection portion includes the resin particles described above. It is preferable that the material of the connection portion is the above-described conductive particles or the above-described conductive material. It is preferable that the connection portion is formed of the above-described conductive particles or a connection structure formed of the above-described conductive material.

  When the above-mentioned conductive particles are used alone, the connection part itself is a conductive particle. That is, the first and second connection target members are connected by the conductive particles. The conductive material used for obtaining the connection structure is preferably an anisotropic conductive material. It is preferable that the first electrode and the second electrode are electrically connected by the connection portion.

  FIG. 4 is a sectional view showing an example of a connection structure using the conductive particles 1 shown in FIG.

  The connection structure 41 shown in FIG. 4 includes a first connection target member 42, a second connection target member 43, and a connection connecting the first connection target member 42 and the second connection target member 43. A part 44. The connection part 44 is formed of a conductive material containing the conductive particles 1 and a binder. In FIG. 4, the conductive particles 1 are schematically illustrated for convenience of illustration. Instead of the conductive particles 1, other conductive particles such as the conductive particles 21 and 31 may be used.

  The first connection target member 42 has a plurality of first electrodes 42a on the surface (upper surface). The second connection target member 43 has a plurality of second electrodes 43a on the surface (lower surface). The first electrode 42a and the second electrode 43a are electrically connected by one or a plurality of conductive particles 1. Therefore, the first and second connection target members 42 and 43 are electrically connected by the conductive particles 1.

  FIG. 5 is a cross-sectional view illustrating an example of a connection structure using the resin particles according to the present invention.

  The connection structure 51 shown in FIG. 5 includes a first connection target member 52, a second connection target member 53, and an adhesive bonding the first connection target member 52 and the second connection target member 53. And a layer 54.

  The adhesive layer 54 includes the resin particles 11 described above. The resin particles 11 are not in contact with both the first and second connection target members 52 and 53. The resin particles 11 are used as stress relaxation spacers.

  The adhesive layer 54 includes gap control particles 61 and a thermosetting component 62. In the adhesive layer 54, the gap control particles 61 are in contact with both the first and second connection target members 52 and 53. The gap control particles 61 may be conductive particles or particles having no conductivity. The gap control particles may be the resin particles described above. The thermosetting component 62 contains a thermosetting compound and a thermosetting agent. The thermosetting component 62 is a cured product of a thermosetting compound. The thermosetting component 62 is formed by curing a thermosetting compound.

  The first connection target member may have a first electrode on a surface. The second connection target member may have a second electrode on a surface.

The method for manufacturing the connection structure is not particularly limited. As an example of a method of manufacturing the connection structure, a method of disposing the conductive material between a first connection target member and a second connection target member, obtaining a laminate, and then heating and pressing the laminate. And the like. The pressure at the time of pressurization is about 9.8 × 10 ⁴ Pa to 4.9 × 10 ⁶ Pa. The temperature at the time of the heating is about 120 ° C to 220 ° C. The pressure at the time of pressurization for connecting the electrodes of the flexible printed circuit board, the electrodes arranged on the resin film, and the electrodes of the touch panel is about 9.8 × 10 ⁴ Pa to 1.0 × 10 ⁶ Pa.

  Specific examples of the connection target member include electronic components such as a semiconductor chip, a capacitor and a diode, and electronic components such as a circuit board such as a printed board, a flexible printed board, a glass epoxy board, and a glass board. Preferably, the connection target member is an electronic component. It is preferable that at least one of the first connection target member and the second connection target member is a semiconductor wafer or a semiconductor chip. The connection structure is preferably a semiconductor device.

  The conductive material is preferably a conductive material for connecting electronic components. The conductive paste is a paste-like conductive material, and is preferably applied to the connection target member in a paste-like state.

  The conductive particles, the conductive material, and the adhesive are suitably used for touch panels. Therefore, it is also preferable that the connection target member is a flexible substrate or a connection target member having electrodes disposed on the surface of a resin film. The connection target member is preferably a flexible substrate, and is preferably a connection target member having electrodes disposed on a surface of a resin film. When the flexible substrate is a flexible printed substrate or the like, the flexible substrate generally has electrodes on its surface.

  Examples of the electrodes provided on the connection target member include metal electrodes such as a gold electrode, a nickel electrode, a tin electrode, an aluminum electrode, a silver electrode, a SUS electrode, a copper electrode, a molybdenum electrode, and a tungsten electrode. When the member to be connected is a flexible printed circuit board, the electrode is preferably a gold electrode, a nickel electrode, a tin electrode or a copper electrode. When the member to be connected is a glass substrate, the electrode is preferably an aluminum electrode, a copper electrode, a molybdenum electrode, or a tungsten electrode. When the electrode is an aluminum electrode, the electrode may be an electrode formed only of aluminum, or may be an electrode in which an aluminum layer is laminated on a surface of a metal oxide layer. Examples of the material of the metal oxide layer include indium oxide doped with a trivalent metal element and zinc oxide doped with a trivalent metal element. Examples of the trivalent metal element include Sn, Al, and Ga.

(Liquid crystal display device)
The resin particles can be suitably used as a spacer for a liquid crystal display element.

  The liquid crystal display element according to the present invention includes a first liquid crystal display element member, a second liquid crystal display element member, the first liquid crystal display element member, and the second liquid crystal display element member. And a spacer disposed therebetween. The spacer is the resin particles described above.

  The liquid crystal display element includes a first liquid crystal display element member and a second liquid crystal display element member in a state where the first liquid crystal display element member and the second liquid crystal display element member face each other. A seal portion for sealing the outer periphery of the member may be provided.

  The resin particles can be used as a peripheral sealant for a liquid crystal display element. The liquid crystal display element includes a first liquid crystal display element member, a second liquid crystal display element member, and a state in which the first liquid crystal display element member and the second liquid crystal display element member face each other. A sealing portion for sealing the outer periphery of the first liquid crystal display element member and the second liquid crystal display element member. The liquid crystal display element includes a liquid crystal disposed between the first liquid crystal display element member and the second liquid crystal display element member inside the seal portion. In this liquid crystal display element, a liquid crystal dropping method is applied, and the seal portion is formed by thermosetting a sealant for the liquid crystal dropping method.

  FIG. 6 is a cross-sectional view showing one example of a liquid crystal display device using the resin particles according to the present invention as a spacer for a liquid crystal display device.

The liquid crystal display element 81 shown in FIG. 6 has a pair of transparent glass substrates 82. The transparent glass substrate 82 has an insulating film (not shown) on the opposite surface. As a material of the insulating film, for example, SiO ₂ or the like can be used. A transparent electrode 83 is formed on the transparent glass substrate 82 on the insulating film. Examples of the material of the transparent electrode 83 include ITO. The transparent electrode 83 can be formed by patterning, for example, by photolithography. An alignment film 84 is formed on the transparent electrode 83 on the surface of the transparent glass substrate 82. Examples of the material of the alignment film 84 include polyimide.

  Liquid crystal 85 is sealed between the pair of transparent glass substrates 82. A plurality of resin particles 11 are arranged between the pair of transparent glass substrates 82. The resin particles 11 are used as liquid crystal display element spacers. The interval between the pair of transparent glass substrates 82 is regulated by the plurality of resin particles 11. A sealant 86 is arranged between the edges of the pair of transparent glass substrates 82. The sealant 86 prevents the liquid crystal 85 from flowing out. The sealant 86 includes resin particles 11A that differ only in particle size from the resin particles 11.

In the above-mentioned liquid crystal display element, the arrangement density of the liquid crystal display element spacers per 1 mm ² is preferably 10 pieces / mm ² or more, and more preferably 1000 pieces / mm ² or less. When the arrangement density is 10 cells / mm ² or more, the cell gap becomes even more uniform. When the arrangement density is 1000 / mm ² or less, the contrast of the liquid crystal display element is further improved.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited only to the following examples.

(Example 1)
(1) Preparation of resin particles Polystyrene particles having an average particle diameter of 6.0 μm were prepared as seed particles. 5.0 parts by weight of the polystyrene particles, 900 parts by weight of ion-exchanged water, and 170 parts by weight of a 5% by weight aqueous solution of polyvinyl alcohol were mixed to prepare a mixed solution. After the above liquid mixture was dispersed by ultrasonic waves, it was placed in a separable flask and stirred uniformly.

  Further, cyclohexyl methacrylate is prepared as the first polymerizable compound 1 having one polymerizable functional group and having a cyclic organic group, and having one polymerizable functional group and having a cyclic organic group. Isobornyl acrylate was prepared as 1 polymerizable compound 2. Further, divinylbenzene was prepared as a second polymerizable compound having two or more polymerizable functional groups and having a cyclic organic group.

  Next, 9 parts by weight of polytetramethylene glycol diacrylate, 1 part by weight of divinylbenzene, 15 parts by weight of cyclohexyl methacrylate, and 75 parts by weight of isobornyl acrylate were mixed to obtain a mixture. To the obtained mixture, 6.0 parts by weight of benzoyl peroxide ("Niper BW" manufactured by NOF CORPORATION) was added, and further, 1000 parts by weight of ion-exchanged water was added to prepare an emulsion.

  The emulsion was further added to the mixture in the separable flask, and the mixture was stirred for 16 hours to allow the seed particles to absorb the monomer, thereby obtaining a suspension containing the seed particles in which the monomer was swollen.

  Thereafter, 510 parts by weight of a 5% by weight aqueous solution of polyvinyl alcohol was added, heating was started and the reaction was carried out at 85 ° C. for 10 hours to obtain resin particles.

(2) Preparation of conductive particles The obtained resin particles were washed, subjected to a classification operation, and then dried. Then, a nickel layer was formed on the surface of the obtained resin particles by electroless plating to produce conductive particles. The thickness of the nickel layer was 0.1 μm.

(3) Preparation of conductive material (anisotropic conductive paste) In order to prepare a conductive material (anisotropic conductive paste), the following materials were prepared.

(Material of conductive material (anisotropic conductive paste))
Thermosetting compound A: Epoxy compound ("EP-3300P" manufactured by Nagase ChemteX Corporation)
Thermosetting compound B: epoxy compound ("DICPIC HP-4032D" manufactured by DIC)
Thermosetting compound C: Epoxy compound (“Epogoose PT” manufactured by Yokkaichi Gosei Co., Ltd., polytetramethylene glycol diglycidyl ether)
Thermosetting agent: Thermal cation generator (San Aid “SI-60” manufactured by Sanshin Chemical Co., Ltd.)
Filler: silica (average particle size 0.25 μm)

  A conductive material (anisotropic conductive paste) was produced as follows.

(Method of producing conductive material (anisotropic conductive paste))
10 parts by weight of the thermosetting compound A, 10 parts by weight of the thermosetting compound B, 15 parts by weight of the thermosetting compound C, 5 parts by weight of the thermosetting agent, and 20 parts by weight of the filler were obtained to obtain a blend. Further, after adding the obtained conductive particles so that the content in the formulation 100% by weight becomes 10% by weight, the mixture is stirred at 2,000 rpm for 5 minutes using a planetary stirrer to thereby form a conductive material (anisotropically). Conductive paste).

(4) Preparation of Connection Structure As a first connection target member, a glass substrate having an aluminum electrode pattern having an L / S of 20 μm / 20 μm on the upper surface was prepared. Further, as a second connection target member, a semiconductor chip having a gold electrode pattern (gold electrode thickness: 20 μm) having an L / S of 20 μm / 20 μm on the lower surface was prepared.

  A conductive material (anisotropic conductive paste) immediately after fabrication was applied on the upper surface of the glass substrate so as to have a thickness of 30 μm to form a conductive material (anisotropic conductive paste) layer. Next, the semiconductor chip was stacked on the upper surface of the conductive material (anisotropic conductive paste) layer so that the electrodes faced each other. Then, while adjusting the temperature of the head so that the temperature of the conductive material (anisotropic conductive paste) layer is 170 ° C., the pressure heating head is placed on the upper surface of the semiconductor chip, and the conductive material (anisotropic conductive paste) The layer was cured at 170 ° C., 1.0 MPa, and 15 seconds to obtain a connection structure.

(Example 2)
When preparing resin particles, 9 parts by weight of polytetramethylene glycol diacrylate was changed to 91 parts by weight of methyl methacrylate, and the blending amount of cyclohexyl methacrylate was changed from 15 parts by weight to 5 parts by weight, and isobornyl acrylate was changed. Was changed from 75 parts by weight to 3 parts by weight. Except for the above changes, conductive particles, conductive materials, and connection structures were obtained in the same manner as in Example 1.

(Example 3)
The conductive particles and the conductive material were prepared in the same manner as in Example 1, except that 9 parts by weight of polytetramethylene glycol diacrylate was changed to 9 parts by weight of 2-methacryloxyethyl acid phosphate when preparing the resin particles. And a connection structure.

(Example 4)
When producing resin particles, conductive particles, a conductive material and a connection structure were obtained in the same manner as in Example 2, except that 5 parts by weight of cyclohexyl methacrylate was changed to 5 parts by weight of phenoxyethylene glycol methacrylate. .

(Example 5)
Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in Example 2, except that 5 parts by weight of cyclohexyl methacrylate was changed to 5 parts by weight of dicyclopentenyl acrylate when producing resin particles. .

(Example 6)
When preparing the resin particles, the conductive particles, the conductive material and the connection structure were changed in the same manner as in Example 1 except that 1 part by weight of divinylbenzene was changed to 1 part by weight of tricyclodecane dimethanol diacrylate. Obtained.

(Comparative Example 1)
When preparing the resin particles, the same procedure as in Example 1 was performed except that the amount of polytetramethylene glycol diacrylate was changed from 9 parts by weight to 10 parts by weight, and that no divinylbenzene was added. Thus, a conductive particle, a conductive material, and a connection structure were obtained.

(Comparative Example 2)
When preparing resin particles, 9 parts by weight of polytetramethylene glycol diacrylate was changed to 94 parts by weight of methyl methacrylate, and the blending amount of cyclohexyl methacrylate was changed from 15 parts by weight to 5 parts by weight. Was changed not to be blended. Except for the above changes, conductive particles, conductive materials, and connection structures were obtained in the same manner as in Example 1.

(Comparative Example 3)
When preparing the resin particles, the amount of polytetramethylene glycol diacrylate was changed from 9 parts by weight to 50 parts by weight, and the amount of isobornyl acrylate was changed from 75 parts by weight to 34 parts by weight. Except for the above, a conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Example 1.

(Comparative Example 4)
When producing resin particles, a conductive particle, a conductive material, and a connection structure were obtained in the same manner as in Comparative Example 1 except that 15 parts by weight of cyclohexyl methacrylate was changed to 15 parts by weight of phenoxyethylene glycol methacrylate. .

(Evaluation)
(1) Content of structure derived from first polymerizable compound (WM) and content of structure derived from second polymerizable compound (WD)
From the compounding amounts of the first and second polymerizable compounds used in obtaining the polymer and the remaining amount of the first and second polymerizable compounds after polymerization, the polymerized first and second polymerizable compounds are obtained. The content (WM) of the structure derived from the first polymerizable compound and the content (WD) of the structure derived from the second polymerizable compound of the obtained resin particles were calculated. The weight ratio (WM / WD) of the content (WM) of the structure derived from the first polymerizable compound to the content (WD) of the structure derived from the second polymerizable compound was calculated.

(2) Particle Size The particle size of the obtained resin particles (particle size before heating) was measured using a particle size distribution analyzer (“Multisizer 4” manufactured by Beckman Coulter, Inc.) to measure the particle size of about 100,000 resin particles. Then, the average value was calculated.

  Next, the resin particles used for measuring the particle diameter were heated at 150 ° C. for 1000 hours. The particle size of the resin particles after heating for 1000 hours was measured by the method described above. From the obtained measurement results, the ratio of the particle size of the resin particles after heating to the particle size of the resin particles before heating (particle size of resin particles after heating / particle size of resin particles before heating) was calculated.

(3) 10% K value and 30% K value The 10% K value and 30% K value (30% K value before heating) of the obtained resin particles were measured by the method described above.

  Next, the resin particles used for measuring the 30% K value were heated at 150 ° C. for 1000 hours. The 30% K value of the resin particles after heating for 1000 hours was measured by the method described above. From the obtained measurement results, the ratio of the 30% K value after heating to the 30% K value before heating (30% K value after heating / 30% K value before heating) was calculated.

(4) Compression recovery rate at 60% compression deformation The compression recovery rate at 60% compression deformation of the obtained resin particles was measured by the method described above.

(5) Plating state The obtained conductive particles were heated at 150 ° C. for 1000 hours. The state of plating of 50 conductive particles after heating was observed with a scanning electron microscope. The presence or absence of plating unevenness such as plating cracking or plating peeling was evaluated. The plating state was determined based on the following criteria.

[Plating condition judgment criteria]
○: Less than three conductive particles with uneven plating ○: Three or more and less than six conductive particles with uneven plating ：: Six or more conductive particles with uneven plating

(6) Connection strength The connection strength at 260 ° C. of the obtained connection structure was measured using a mount strength measurement device. The connection strength was determined based on the following criteria.

[Judgment criteria for connection strength]
○: Shear strength is 150 N / cm ² or more 〇: Shear strength is 100 N / cm ² or more and less than 150 N / cm ² ×: Shear strength is less than 100 N / cm ²

(7) Springback A scanning electron microscope was used to observe whether or not springback had occurred at the connection portion of the obtained connection structure. Springback was determined based on the following criteria.

[Springback criteria]
○: No springback has occurred ×: Springback has occurred

(8) Cooling / heating cycle characteristics (connection reliability)
The obtained connection structure was heated from −65 ° C. to 150 ° C. and cooled / cooled to −65 ° C. as one cycle. The presence or absence of floating or peeling at the connection was observed by an ultrasonic flaw detector (SAT). The thermal cycle characteristics (connection reliability) were determined based on the following criteria.

[Criteria for cooling / heating cycle characteristics (connection reliability)]
：: No floating or peeling at the connecting part ×: Floating or peeling at the connecting part

  The results are shown in Tables 1, 2 and 3 below.

(9) Example of use as spacer for liquid crystal display element Fabrication of STN type liquid crystal display element:
In a dispersion medium containing 70 parts by weight of isopropyl alcohol and 30 parts by weight of water, the spacers (resin particles) for liquid crystal display elements of Examples 1 to 6 having a solid content of 2% by weight in 100% by weight of the obtained spacer dispersion liquid. And stirred to obtain a liquid crystal display element spacer dispersion.

After depositing a SiO ₂ film on one surface of a pair of transparent glass plates (50 mm in length, 50 mm in width, and 0.4 mm in thickness) by a CVD method, an ITO film was formed on the entire surface of the SiO ₂ film by sputtering. A polyimide alignment film composition (SE3510, manufactured by Nissan Chemical Industries, Ltd.) was applied to the obtained glass substrate with an ITO film by spin coating, and baked at 280 ° C. for 90 minutes to form a polyimide alignment film. After the rubbing treatment was performed on the alignment film, liquid crystal display element spacers were wet-sprayed on the alignment film side of one of the substrates so that the number of spacers was 100 per 1 mm ² . After a sealant was formed around the other substrate, this substrate and the substrate on which the spacers were scattered were disposed so as to face each other so that the rubbing direction was 90 °, and the two were bonded together. Thereafter, the sealant was cured by treating at 160 ° C. for 90 minutes to obtain an empty cell (a screen containing no liquid crystal). An STN-type liquid crystal (manufactured by DIC) containing a chiral agent is injected into the obtained empty cell, and then the injection port is closed with a sealing agent. Obtained.

  In the obtained liquid crystal display element, the distance between the substrates was well regulated by the liquid crystal display element spacers (resin particles) of Examples 1 to 6. In addition, the liquid crystal display element showed good display quality. The display quality of the obtained liquid crystal display element was good even when the resin particles of Examples 1 to 6 were used as a spacer for the liquid crystal display element as a peripheral sealant for the liquid crystal display element.

DESCRIPTION OF SYMBOLS 1 ... Conductive particle 2 ... Conductive part 11 ... Resin particle 11A ... Resin particle 21 ... Conductive particle 22 ... Conductive part 22A ... First conductive part 22B ... Second conductive part 31 ... Conductive particle 31a ... Projection 32 ... Conductive portion 32a Projection 33 Core material 34 Insulating material 41 Connection structure 42 First member to be connected 42a First electrode 43 Second member to be connected 43a Second electrode 44 Connection Part 51: Connection structure 52: First member to be connected 53: Second member to be connected 54: Adhesive layer 61: Gap control particle 62: Thermosetting component 81: Liquid crystal display element 82: Transparent glass substrate 83: Transparent Electrode 84: Alignment film 85: Liquid crystal 86: Sealant

Claims (15)

The overlap between the first polymerizable compound having one polymerizable functional group and having a cyclic organic group and the second polymerizable compound having two or more polymerizable functional groups and having a cyclic organic group. Coalescing,
The weight ratio of the content of the structure derived from the first polymerizable compound to the content of the structure derived from the second polymerizable compound is 7 or more,
When the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the particle size of the resin particles after heating to the particle size of the resin particles before heating is 0.9 or less.   The resin particles according to claim 1, wherein a compression recovery rate when subjected to 60% compression deformation is 10% or less. The resin particles according to claim 1, wherein the 10% K value is 3000 N / mm ² or less. 30% K value is 1500 N / mm ² or less, the resin particles according to any one of claims 1 to 3.   When the resin particles are heated at 150 ° C. for 1000 hours, the ratio of the 30% K value of the heated resin particles to the 30% K value of the resin particles before heating is 0.8 or more and 1.5 or less. Item 5. The resin particles according to any one of Items 1 to 4.   The resin particles according to any one of claims 1 to 5, wherein the cyclic organic group in the first polymerizable compound and the cyclic organic group in the second polymerizable compound are each a hydrocarbon group.   The resin particle according to any one of claims 1 to 6, wherein the cyclic organic group in the first polymerizable compound is a phenylene group, a cyclohexyl group, or an isobornyl group.   The resin particles according to any one of claims 1 to 7, wherein the cyclic organic group in the second polymerizable compound is a phenylene group, a cyclohexyl group, or an isobornyl group.   The resin particles according to claim 1, further comprising an acid phosphate compound.   The resin particle according to any one of claims 1 to 9, which is used as a spacer or a conductive part is formed on a surface and used to obtain conductive particles having the conductive part. The resin particles according to any one of claims 1 to 10,
A conductive portion disposed on a surface of the resin particle. Including conductive particles and a binder,
A conductive material, wherein the conductive particles include the resin particles according to claim 1 and a conductive portion disposed on a surface of the resin particles. The resin particles according to any one of claims 1 to 10,
An adhesive containing a binder. A first connection target member having a first electrode on its surface;
A second member to be connected having a second electrode on its surface;
The first connection target member, and a connection portion that connects the second connection target member,
The material of the connection portion includes the resin particles according to any one of claims 1 to 10,
A connection structure, wherein the first electrode and the second electrode are electrically connected by the connection portion. A first liquid crystal display element member;
A second liquid crystal display element member;
A spacer disposed between the first liquid crystal display element member and the second liquid crystal display element member;
A liquid crystal display device, wherein the spacer is a resin particle according to any one of claims 1 to 10.

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