阅读说明：本技术 树脂粒子、导电性粒子、导电材料及连接结构体 (Resin particle, conductive material, and connection structure ) 是由 森田弘幸 胁屋武司 于 2020-03-18 设计创作，主要内容包括：本发明提供一种树脂粒子,该树脂粒子可以均匀地接触粘附体,且使用表面上形成有导电部的导电性粒子使电极间实现了电连接时可以有效地提高与导电部的密合性和抗冲击性,同时还可以有效地降低连接电阻。本发明涉及一种树脂粒子,其通过在大气气氛下以5℃/分钟的升温速度将树脂粒子从100℃加热至350℃来进行差示扫描量热测定时观察到放热峰。(The invention provides a resin particle which can uniformly contact an adherend, can effectively improve the adhesion and impact resistance with a conductive part when electric connection is realized between electrodes by using the conductive particle with the conductive part formed on the surface, and can effectively reduce the connection resistance. The present invention relates to a resin particle in which an exothermic peak is observed when a differential scanning calorimetry measurement is performed by heating the resin particle from 100 ℃ to 350 ℃ at a temperature increase rate of 5 ℃/min under an atmospheric atmosphere.)

1. A resin particle in which an exothermic peak is observed when a differential scanning calorimetry is performed by heating the resin particle from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min under an atmospheric atmosphere.

2. The resin particle according to claim 1, wherein an exothermic amount of an exothermic peak having a maximum peak area among the exothermic peaks is 2000mJ/mg or more and 25000mJ/mg or less.

3. The resin particle as claimed in claim 1 or 2, wherein an endothermic peak having an endothermic amount of 2000mJ/mg or more is not observed when a differential scanning calorimetry measurement is performed by heating the resin particle from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min under an atmospheric atmosphere.

4. The resin particles according to any one of claims 1 to 3, wherein the absolute value of the difference between the compression elastic modulus when the resin particles are compressed by 10% and the compression elastic modulus when the resin particles are compressed by 10% after being heated at 200 ℃ for 10 minutes is 180N/mm²The above.

5. The resin particle according to any one of claims 1 to 4, which is used for a spacer, an adhesive for electronic parts, a conductive particle having a conductive portion, or a material for laminate molding.

6. The resin particle according to any one of claims 1 to 5, which is used as a spacer or for forming a conductive portion on a surface to obtain a conductive particle having the conductive portion.

7. A conductive particle comprising:

the resin particle as claimed in any one of claims 1 to 6, and

and a conductive portion disposed on a surface of the resin particle.

8. The conductive particle according to claim 7, wherein the absolute value of the difference between the compression elastic modulus when the conductive particle is compressed by 10% and the compression elastic modulus when the conductive particle is compressed by 10% after being heated at 200 ℃ for 10 minutes is 180N/mm²The above.

9. The conductive particle according to claim 7 or 8, further comprising an insulating material disposed on an outer surface of the conductive portion.

10. The conductive particle according to any one of claims 7 to 9, which has a protrusion on an outer surface of the conductive portion.

11. A conductive material comprising conductive particles and a binder resin, wherein,

the conductive particles comprise the resin particles according to any one of claims 1 to 6, and a conductive portion disposed on the surface of the resin particles.

12. A connection structure body is provided with:

a first member to be connected having a first electrode on the surface thereof,

A second connection object member having a second electrode on the surface thereof, and

a connecting portion that connects the first connection target member and the second connection target member together, wherein,

the connecting portion is formed of conductive particles or a conductive material containing the conductive particles and a binder resin,

the conductive particles comprising the resin particles according to any one of claims 1 to 6 and a conductive portion disposed on the surface of the resin particles,

the first electrode and the second electrode are electrically connected by the conductive particles.

Technical Field

The present invention relates to a resin particle having good compression characteristics. The present invention also relates to conductive particles, a conductive material, and a connection structure using the resin particles.

Background

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

The anisotropic conductive material is used for electrically connecting electrodes of various connection target members such as a flexible printed circuit board (FPC), a glass substrate, a glass epoxy board, and a semiconductor chip to obtain a connection structure. As the conductive particles, conductive particles having base particles and a conductive layer disposed on the surface of the base particles can be used. Resin particles can be used as the base particles.

Patent document 1 discloses a resin particle that is present on the surface of a conductive particle and is used to insulate the conductive particle. The resin particles contain an acrylic crosslinked polymer obtained by copolymerizing a polymerizable component containing: a non-crosslinkable alkyl (meth) acrylate (A) having an alkyl group having 4 to 18 carbon atoms and a crosslinkable monomer (B) having two or more polymerizable groups in one molecule. In the resin particles, the content of the crosslinkable monomer (B) is 7% by mass or more in the polymerizable component.

Patent document 2 below discloses a method for producing thermosetting resin softening particles. The manufacturing method comprises the following steps: the method comprises a step of reacting a monomer compound containing at least one bifunctional monomer with an aldehyde compound in a colloidal silica suspension having an average particle diameter of 5 to 70nm under alkaline conditions to form an aqueous solution of a soluble initial condensate in water, and a step of adding an acid catalyst to the aqueous solution to precipitate spherical thermosetting resin softening particles. In the above production method, the bifunctional monomer is a monomer selected from the group consisting of 6-substituted guanamines and ureas.

In addition, various adhesives are used for bonding two connection target members (adherends). In order to make the thickness of the adhesive layer formed by the adhesive uniform and to control the equal interval (gap) between the two members to be connected (adherends), a gap material (spacer) may be formulated in the adhesive. Resin particles are sometimes used as the gap material (spacer).

Documents of the prior art

Patent document

Patent document 1, Japanese patent laid-open No. 2012 and 124035

Patent document 2 WO2012/067072A1

Disclosure of Invention

Problems to be solved by the invention

In recent years, it has been widely desired that, even when an electrical connection between electrodes is performed using a conductive material containing conductive particles and a connecting material, the electrical connection between the electrodes can be reliably performed under a low pressure, and the connection resistance can be reduced. For example, in a manufacturing method of a liquid crystal display device, in the fog (film On glass) method, when a flexible substrate is mounted, an anisotropic conductive material is disposed On a glass substrate, and the flexible substrate is laminated and thermocompression bonded. In recent years, the frame of a liquid crystal display panel has become narrower, and the glass substrate has been made thinner. In this case, when the flexible substrate is mounted, if thermocompression bonding is performed under high pressure and high temperature conditions, the flexible substrate is deformed, and display unevenness may occur. Therefore, in the FOG system, it is preferable to perform thermocompression bonding with a low pressure when mounting the flexible substrate. Further, even if a method other than the FOG method is used, it is necessary to control the pressure and temperature at the time of thermocompression bonding to low levels.

When conventional resin particles are used as the conductive particles, the connection resistance increases when the electrodes are electrically connected under a low pressure condition. This is caused by insufficient contact of the conductive particles with the electrode (adherend), poor adhesion between the resin particles and the conductive portion disposed on the surface of the resin particles, and peeling of the conductive portion. Further, when a connection portion for electrically connecting electrodes is formed using conventional conductive particles, the connection resistance increases due to peeling or the like of a conductive portion disposed on the surface of the resin particle when an impact such as dropping is applied to the connection portion.

In addition, in the conventional conductive particles, the conductive particles do not sufficiently contact the electrode (adherend) and the connection resistance is increased depending on the hardness (material) of the electrode (adherend) not only by the pressure at the time of connection. In addition, a flaw is formed on the surface of the electrode (adherend), resulting in an increase in connection resistance.

In addition, when conventional resin particles are used as the gap material (spacer), the member to be connected (adherend) may be damaged. In addition, when conventional resin particles are used, the resin particles cannot sufficiently contact a member to be connected (adherend), and a sufficient gap control effect cannot be obtained.

An object of the present invention is to provide resin particles which can uniformly contact an adherend, can effectively improve adhesion to a conductive portion and impact resistance when electrical connection is established between electrodes using conductive particles having a conductive portion formed on the surface thereof, and can further effectively reduce connection resistance. Another object of the present invention is to provide conductive particles, a conductive material, and a connection structure using the resin particles.

Means for solving the problems

According to a broad aspect of the present invention, there is provided a resin particle in which an exothermic peak is observed when a differential scanning calorimetry measurement is performed by heating the resin particle from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/minute under an atmospheric atmosphere.

According to a specific aspect of the resin particle of the present invention, an exothermic amount of an exothermic peak having a maximum peak area among the exothermic peaks is 2000mJ/mg or more and 25000mJ/mg or less.

According to a specific aspect of the resin particle of the present invention, an endothermic peak having an endothermic amount of 2000mJ/mg or more is not observed when the differential scanning calorimetry is performed by heating the resin particle from 100 ℃ to 350 ℃ at a temperature increase rate of 5 ℃/min under an atmospheric atmosphere.

According to a specific aspect of the resin particles of the present invention, the absolute value of the difference between the compression elastic modulus when the resin particles are compressed by 10% and the compression elastic modulus when the resin particles are compressed by 10% after being heated at 200 ℃ for 10 minutes is 180N/mm²The above.

According to a specific aspect of the resin particle according to the present invention, the resin particle is used for a spacer, an adhesive for electronic components, a conductive particle having a conductive portion, or a material for laminate molding.

According to a specific aspect of the resin particle according to the present invention, the resin particle is used as a spacer or for forming a conductive portion on a surface to obtain a conductive particle having the conductive portion.

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

According to a specific aspect of the conductive particle of the present invention, an absolute value of a difference between a compression elastic modulus when the conductive particle is compressed by 10% and a compression elastic modulus when the conductive particle is compressed by 10% after being heated at 200 ℃ for 10 minutes is 180N/mm²The above.

According to a specific aspect of the conductive particle according to the present invention, the conductive particle further includes an insulating material disposed on an outer surface of the conductive portion.

According to a specific aspect of the conductive particle according to the present invention, the conductive portion has a protrusion on an outer surface thereof.

According to a broad aspect of the present invention, there is provided a conductive material comprising conductive particles and a binder resin, wherein the conductive particles comprise the resin particles described above and a conductive portion disposed on the surface of the resin particles.

According to a broad aspect of the present invention, there is provided a connection structure comprising: the present invention provides a connector for a semiconductor device, the connector including a first component to be connected having a first electrode on a surface thereof, a second component to be connected having a second electrode on a surface thereof, and a connecting portion for connecting the first component to be connected and the second component to be connected, wherein the connecting portion is formed of conductive particles or a conductive material containing the conductive particles and a binder resin, the conductive particles include the resin particles and a conductive portion disposed on a surface of the resin particles, and the first electrode and the second electrode are electrically connected by the conductive particles.

ADVANTAGEOUS EFFECTS OF INVENTION

The resin particles according to the present invention have an exothermic peak observed when the resin particles are heated from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min in an atmospheric atmosphere to perform differential scanning calorimetry. The resin particles according to the present invention, having the above-described structure, can uniformly contact an adherend, and when electrical connection is established between electrodes using conductive particles having a conductive portion formed on the surface thereof, can effectively improve adhesion to the conductive portion and impact resistance, and can effectively reduce connection resistance.

Drawings

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

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

Fig. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention.

Fig. 4 is a cross-sectional view showing an example of a connection structure using conductive particles according to the first embodiment of the present invention.

Fig. 5 is a cross-sectional view showing an example of an electronic component device using the resin particles according to the present invention.

Fig. 6 is an enlarged sectional view of a joint portion in the electronic component device shown in fig. 5.

Detailed Description

The present invention will be described in detail below.

(resin particles)

The resin particles according to the present invention have an exothermic peak observed when the resin particles are heated from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min in an atmospheric atmosphere to perform differential scanning calorimetry.

The resin particles according to the present invention, which have the above-described configuration, can uniformly contact an adherend, and when the conductive particles having the conductive portions formed on the surfaces thereof are used to electrically connect electrodes, can effectively improve the adhesion to the conductive portions and the impact resistance, and can effectively reduce the connection resistance.

The resin particles of the present invention can be thermally cured by heating because an exothermic peak is observed by differential scanning calorimetry. The resin particles according to the present invention (resin particles before heat curing) are not completely heat cured, and therefore easily deformed under relatively low pressure and temperature conditions. Therefore, when the conductive particles having the conductive portions formed on the surfaces of the resin particles are used to electrically connect the electrodes, the conductive particles can be sufficiently brought into contact with the electrodes even when the pressure and temperature at the time of thermocompression bonding are set at low levels, and the formation of scratches on the electrodes can be prevented. In the case where the conductive particles having the conductive portions formed on the surfaces of the resin particles according to the present invention are used to form the connection portions for electrically connecting the electrodes, the resin particles may be thermally cured in a compressed state during thermocompression bonding. Since the conductive particles in the connecting portion maintain a compressed shape, peeling of the conductive portion can be effectively prevented, and adhesion between the resin particles and the conductive portion can be effectively improved. Further, even if an impact such as dropping is applied to the connection portion, the conductive portion can be effectively prevented from peeling off, and the connection resistance between the electrodes can be effectively reduced. The conductive particles using the resin particles according to the present invention can effectively improve impact resistance. In addition, the conductive particles using the resin particles according to the present invention can effectively reduce the connection resistance between electrodes and can effectively improve the connection reliability between electrodes. For example, even when a connection structure in which the electrical connection between electrodes is achieved by using conductive particles of the resin particles according to the present invention is left under high temperature and high humidity conditions for a long time, the connection resistance is further less likely to increase, and poor conductivity is further less likely to occur.

In addition, when the resin particles according to the present invention are used as a gap material (spacer), occurrence of scratches on a member to be connected or the like can be effectively suppressed. Further, the gap control device can be brought into sufficient contact with the member material to be connected, and a sufficient gap control effect can be obtained.

The resin particles according to the present invention have an exothermic peak observed when the resin particles are heated from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min in an atmospheric atmosphere to perform differential scanning calorimetry. The exothermic peak is a peak having an exothermic amount of 1000mJ/mg or more. In the differential scanning calorimetry, 10mg of the resin particles are preferably heated from 100 ℃ to 350 ℃ in an atmospheric atmosphere at a temperature rise rate of 5 ℃/min.

If the resin particles satisfy the above preferred embodiment, the adherend can be more uniformly contacted. Further, when the resin particles satisfy the above preferred embodiment, when the conductive particles having the conductive portion formed on the surface are used to electrically connect electrodes, the adhesion to the conductive portion and the impact resistance can be further effectively improved, and the connection resistance can be further effectively reduced. In general, the curing reaction of a thermosetting resin is an exothermic reaction, and is observed as an exothermic peak in a differential scanning calorimetry. The resin particles are preferably thermally cured by heating.

In the differential scanning calorimetry, only one exothermic peak may be observed, or two or more exothermic peaks may be observed. The exothermic amount of the exothermic peak having the largest peak area among the exothermic peaks observed in the differential scanning calorimetry is preferably 2000mJ/mg or more, more preferably 10000mJ/mg or more, and preferably 25000mJ/mg or less, more preferably 22000mJ/mg or less. When the heat release amount of the heat release peak having the maximum peak area is not less than the lower limit and not more than the upper limit, the resin particles can be more uniformly brought into contact with the adherend. Further, when the heat release amount of the heat release peak having the maximum peak area is not less than the lower limit and not more than the upper limit, when the conductive particles having the conductive portion formed on the surface are used to electrically connect electrodes, the adhesion to the conductive portion and the impact resistance can be further effectively improved, and the connection resistance can be further effectively reduced.

Among the above resin particles, it is preferable that an endothermic peak having an endothermic amount of 2000mJ/mg or more is not observed when the resin particles are heated from 100 ℃ to 350 ℃ at a temperature increase rate of 5 ℃/min under an atmospheric atmosphere to perform differential scanning calorimetry. In the present invention, the endothermic peak means a peak having an endothermic amount of 2000mJ/mg or more. In the differential scanning calorimetry, 10mg of the resin particles are preferably heated from 100 ℃ to 350 ℃ in an atmospheric atmosphere at a temperature rise rate of 5 ℃/min. If the resin particles satisfy the above preferred embodiment, the adherend can be more uniformly contacted. Further, when the resin particles satisfy the above preferred embodiment, when the conductive particles having the conductive portion formed on the surface are used to electrically connect electrodes, the adhesion to the conductive portion and the impact resistance can be further effectively improved, and the connection resistance can be further effectively reduced. In general, melting of a resin or the like is an endothermic reaction, and is observed as an endothermic peak in differential scanning calorimetry. The resin particles are preferably free from melting of resin or the like.

For the differential scanning calorimetry, a differential scanning calorimetry apparatus ("DSC 6220" manufactured by hitachi high and new technologies) or the like is used.

The compression modulus of elasticity when the resin particles were compressed by 10% was set to 10% K value (a). The compression modulus of elasticity at 10% compression of the resin particles after heating at 200 ℃ for 10 minutes was set to 10% K value (B). The absolute value of the difference between the 10% K value (A) and the 10% K value (B) is preferably 180N/mm²Above, more preferably 500N/mm²Above, more preferably 800N/mm²Above, 1000N/mm is particularly preferable²The above. The absolute value of the difference between the 10% K value (A) and the 10% K value (B) is preferably 10000N/mm²More preferably 7500N/mm²The concentration is preferably 5000N/mm or less²The following. When the absolute value of the difference between the 10% K value (a) and the 10% K value (B) is not less than the lower limit and not more than the upper limit, the resin particles can be more uniformly brought into contact with the adherend. When the absolute value of the difference between the 10% K value (a) and the 10% K value (B) is not less than the lower limit and not more than the upper limit, when the conductive particles having the conductive portion formed on the surface are used to electrically connect electrodes, the adhesion between the conductive particles and the conductive portion and the impact resistance can be further effectively improved, and the connection resistance can be further effectively reduced. The absolute value of the difference between the 10% K value (A) and the 10% K value (B) is particularly preferably 200N/mm²Above 3000N/mm²The following. When the absolute value of the difference between the 10% K value (a) and the 10% K value (B) satisfies the preferable range, it is possible to more effectively suppress scratches of the adherend caused by the resin particles and to more uniformly bring the resin particles into contact with the adherend. When the absolute value of the difference between the 10% K value (a) and the 10% K value (B) satisfies the preferable range, when the conductive particles having the conductive portion formed on the surface are used to electrically connect the electrodes, the connection resistance between the electrodes can be effectively reduced, and the connection reliability between the electrodes can be further effectively improved.

The 10% K value (A) is preferably 500N/mm²Above, more preferably 800N/mm²Above, and preferably 6000N/mm²The concentration is more preferably 4000N/mm²The following. When the 10% K value (a) is not less than the lower limit and not more than the upper limit, the generation of scratches on the adherend by the resin particles can be more effectively suppressed, and the resin particles can be more uniformly brought into contact with the adherend. When the 10% K value (a) is not less than the lower limit and not more than the upper limit, when the electrodes are electrically connected using the conductive particles having the conductive portion formed on the surface, the connection resistance can be further effectively reduced, and the connection reliability can be further effectively improved.

The compressive modulus of elasticity (10% K value (a) and 10% K value (B)) of the resin particles can be measured as follows.

Resin particles (a)) were prepared. Further, resin particles (B)) heated at 200 ℃ for 10 minutes were prepared. A resin particle (A) or (B) was compressed on a smooth indenter end face of a cylinder (50 μm in diameter, made of diamond) at 25 ℃ at a compression speed of 0.3 mN/sec under a maximum test load of 20mN using a micro compression tester. The load value (N) and the compression displacement (mm) at this time were measured. The compressive modulus (10% K value (a) or 10% K value (B)) can be obtained from the obtained measurement values according to the following formula. As the micro compression tester, for example, Fisherscope H-100 manufactured by Fisher corporation, and the like can be used. The modulus of elasticity (10% K value (a) or 10% K value (B)) of the resin particles (a) or (B) is preferably calculated by arithmetically averaging the modulus of elasticity (10% K value (a) or 10% K value (B)) of the compression of 50 resin particles (a) or (B) selected arbitrarily.

10% K value (A) or 10% K value (B) (N/mm)²)＝(3/2^1/2)·F·S^-3/2·R^-1/2

F: the load value (N) when the resin particles (A) or (B) are subjected to 10% compressive deformation

S: compression Displacement (mm) when the resin particles (A) or (B) were subjected to 10% compression set

R: radius (mm) of resin particle (A) or (B)

The compressive modulus of elasticity generally and quantitatively represents the hardness of the resin particles. By using the above-described compressive modulus of elasticity, the hardness of the resin particles can be quantitatively and uniquely expressed.

The compression recovery rate of the resin particles is preferably 5% or more, more preferably 8% or more, and preferably 60% or less, more preferably 40% or less. When the compression recovery rate is not less than the lower limit and not more than the upper limit, scratches of the adherend by the resin particles can be more effectively suppressed, and the resin particles can be more uniformly brought into contact with the adherend. When the compression recovery rate is not less than the lower limit and not more than the upper limit, when the conductive particles having the conductive portion formed on the surface are used to electrically connect the electrodes, the connection resistance can be further effectively reduced, and the connection reliability can be effectively improved.

The compression recovery rate of the resin particles can be measured as follows.

Resin particles were scattered on the sample stage. Using a micro compression tester, a load (reverse load value) was applied to 1 scattered resin particle in the center direction of the resin particle until the resin particle was compression-deformed by 30% under a condition of 25 ℃ on the smooth indenter end face of a cylinder (diameter 50 μm, made of diamond). Subsequently, the load was removed up to the initial load value (0.4 mN). The load-compression displacement in the above process is measured, and the compression recovery rate can be obtained according to the following equation. The load speed was set to 0.33 mN/second. As the micro compression tester, for example, Fisherscope H-100 manufactured by Fisher corporation, and the like can be used.

Compression recovery rate (%) [ L2/L1] x 100

L1: compression displacement from a load value at origin to a reverse load value when a load is applied

L2: unload displacement from reverse load value at load release to load value for origin

The use of the resin particles is not particularly limited. The above resin particles are preferably used for various purposes. The resin particles are preferably used for a spacer, an adhesive for electronic parts, a conductive particle having a conductive portion, or a lamination molding material. The resin particles are preferably used as a spacer or for forming a conductive portion on a surface to obtain a conductive particle having the conductive portion. In the conductive particles, the conductive portion is formed on a surface of the resin particle. Preferably, the resin particles are used to form a conductive portion on a surface thereof to obtain conductive particles having the conductive portion. The conductive particles are preferably used for electrically connecting electrodes. The conductive particles described above can also be used as a gap material (spacer).

The resin particles are preferably used for the gap material (spacer) or as the gap material (spacer). Examples of the gap material (spacer) include a spacer for a liquid crystal display element, a spacer for gap control, a spacer for stress relaxation, and a spacer for a light control laminate. The spacer for gap control can be used for gap control of a laminated sheet for securing the height and flatness of a support and an optical member for controlling the gap of an electronic component device and securing the smoothness of a glass surface and the thickness of an adhesive layer. The stress relaxation spacer can be used for stress relaxation of a sensor sheet or the like, stress relaxation of a connecting portion connecting two members to be connected, or the like. Examples of the sensor sheet include a semiconductor sensor sheet. In addition, when the resin particles are used as a gap material (spacer), scratches of a member to be connected or the like can be effectively suppressed. Further, the gap control device can be brought into sufficient contact with a member to be connected or the like, and a sufficient gap control effect can be obtained.

The resin particles are preferably used for a spacer for a liquid crystal display element or a spacer for a liquid crystal display element, and are preferably used for a periphery sealing agent for a liquid crystal display element. In the periphery sealing agent for a liquid crystal display element, the resin particles are preferably used as a spacer. Since the resin particles have good compression deformation characteristics and good compression fracture characteristics, when the resin particles are disposed between substrates as a spacer or when a conductive portion is formed on the surface of the resin particles and used as conductive particles to electrically connect electrodes, the spacer or the conductive particles are effectively disposed between the substrates or between the electrodes. Further, in the resin particles, since scratches of a member for a liquid crystal display element or the like can be suppressed, a contact failure or a display failure is less likely to occur in a liquid crystal display element using the spacer for a liquid crystal display element and a connection structure using the conductive particles.

The resin particles are preferably used for an adhesive for electronic components or an adhesive for electronic components. Examples of the adhesive for electronic components include an adhesive for liquid crystal panels, an adhesive for laminated substrates, an adhesive for substrate circuits, and an adhesive for camera modules. Examples of the laminated substrate include a semiconductor sensor sheet. The resin particles used for the adhesive for electronic components or the resin particles used for the adhesive for electronic components are preferably adhesive resin particles having adhesive properties. When the resin particles are adhesive resin particles, the resin particles can be favorably adhered to the member to be laminated when the resin particles are pressure-bonded and cured. The resin particles are a monomer and are useful as an adhesive for electronic parts. The resin particles can be used as an adhesive for electronic components without using other adhesive components. When the resin particles are used as an adhesive for electronic components, they may be used alone or in combination with other adhesive components. When the resin particles are adhesive resin particles having adhesive properties, they can be used as an adhesive for a spacer and an electronic component. When the resin particles are used as an adhesive for a spacer/electronic component, the physical properties required for the spacer, such as adhesiveness, gap controllability, and stress relaxation property, can be more highly achieved than when the resin particles are made of a material different from that of the spacer and the adhesive.

The resin particles are preferably used for a material for laminate molding. When the resin particles are used as the material for layer formation, for example, a three-dimensional formed object can be formed by three-dimensionally laminating the resin particles, forming the resin particles into a specific shape, and then curing the resin particles.

Further, the above resin particles are preferably used as an inorganic filler, an additive for toner, an impact absorber, or a vibration absorber. For example, the resin particles can be used as a substitute for rubber, springs, or the like.

Other details of the resin particles will be described below. In the present specification, "(meth) acrylate" means one or both of "acrylate" and "methacrylate", and "(meth) acrylic acid" means one or both of "acrylic acid" and "methacrylic acid".

(details of the resin particles are otherwise described)

The material of the resin particles is not particularly limited. The material of the resin particles is preferably an organic material. The resin particles may have a porous structure or a solid structure. The porous structure is a structure having a plurality of pores. The solid structure is a structure having no plurality of pores.

Examples of the organic material include polyolefin resins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polyisobutylene, and polybutadiene; acrylic resins such as polymethyl methacrylate and polymethacrylate; polycarbonate, polyamide, phenol-formaldehyde resin, melamine-formaldehyde resin, benzoguanamine-formaldehyde resin, urea-formaldehyde resin, phenol-formaldehyde resin, melamine resin, benzoguanamine resin, urea resin, epoxy resin, polyurethane resin, isocyanate resin, unsaturated polyester resin, saturated polyester resin, polyethylene terephthalate, polysulfone, polyphenylene sulfide, polyacetal, polyimide, polyamideimide, polyether ether ketone, polyether sulfone, divinylbenzene polymer, divinylbenzene copolymer, and the like. Examples of the divinylbenzene copolymer include a divinylbenzene-styrene copolymer and a divinylbenzene- (meth) acrylate copolymer.

The material of the resin particles is preferably a polymer obtained by polymerizing one or more of an epoxy resin, a melamine resin, a benzoguanamine resin, a polyurethane resin, an isocyanate resin, a polyimide resin, a polyamide resin, a polyamideimide resin, a phenol resin, and a polymerizable monomer having an ethylenically unsaturated group. The material of the resin particles is more preferably a polymer obtained by polymerizing one or more of an epoxy resin, a melamine resin, a benzoguanamine resin, a polyimide resin, a polyamide resin, a polyamideimide resin, a phenol resin, and a polymerizable monomer having an ethylenically unsaturated group. The material of the resin particles is particularly preferably an epoxy resin. If the material of the resin particles satisfies the preferred embodiment described above, the compression characteristics of the resin particles can be further controlled within a preferred range.

When an epoxy resin is used as a material of the resin particles, the epoxy resin is preferably a polyfunctional epoxy resin. Examples of the epoxy resin include 2-functional epoxy resins such as bisphenol a type epoxy resin and bisphenol F type epoxy resin; 3-functional epoxy resins such as triazine type epoxy resins and glycidyl amine type epoxy resins; and 4-functional epoxy resins such as tetraphenolene-type epoxy resins and glycidylamine-type epoxy resins. The epoxy resin may be used alone or in combination of two or more.

When an epoxy resin is used as a material of the resin particles, a curing agent is preferably used together with the epoxy resin. The curing agent thermally cures the epoxy resin. The curing agent is not particularly limited. Examples of the curing agent include thiol curing agents such as imidazole curing agents, amine curing agents, phenol curing agents, and polythiol curing agents, and acid anhydride curing agents. One or more of the above thermosetting agents may be used in combination. The curing agent is preferably an amine curing agent from the viewpoint of more easily controlling the compression characteristics of the resin particles within a preferred range.

The above imidazole curing agent is not particularly limited. Examples of the imidazole curing agent include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2, 4-diamino-6- [2 '-methylimidazolyl- (1') ] -ethyl-s-triazine isocyanuric acid adduct, 2-phenyl-4, 5-dimethyloimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2-phenyl-4-benzyl-5-hydroxymethylimidazole, 2-methyl-4-benzyl-5-hydroxymethylimidazole, and mixtures thereof, An imidazole compound in which the hydrogen at the 5-position of 1H-imidazole in 2-p-tolyl-4-methyl-5-hydroxymethylimidazole, 2-m-benzyl-4, 5-dihydroxymethylimidazole, 2-p-benzyl-4, 5-dihydroxymethylimidazole or the like is substituted with a hydroxymethyl group and the hydrogen at the 2-position thereof is substituted with a phenyl group or a benzyl group.

The thiol curing agent is not particularly limited. Examples of the thiol curing agent include trimethylolpropane tris-3-mercaptopropionate, pentaerythritol tetrakis-3-mercaptopropionate, and dipentaerythritol hexa-3-mercaptopropionate.

The above amine curing agent is not particularly limited. Examples of the amine curing agent include ethylenediamine, hexamethylenediamine, octamethylenediamine, decamethylenediamine, 3, 9-bis (3-aminopropyl) -2,4,8, 10-tetraspiro [5.5] undecane, bis (4-aminocyclohexyl) methane, phenylenediamine, 2-bis [4- (4-aminophenoxy) phenyl ] propane, m-phenylenediamine, diaminodiphenylmethane, diaminophenyl ether, m-xylylenediamine, diaminonaphthalene, bisaminomethylcyclohexane, and diaminodiphenylsulfone. The amine curing agent is preferably a diamine compound from the viewpoint of more easily controlling the compression characteristics of the resin particles within a preferred range. The diamine compound is preferably ethylenediamine, hexamethylenediamine, octamethylenediamine, m-phenylenediamine, diaminodiphenylsulfone, phenylenediamine or 2, 2-bis [4- (4-aminophenoxy) phenyl ] propane. From the viewpoint of more easily controlling the compression characteristics of the resin particles within a preferred range, the amine curing agent is more preferably ethylenediamine, diaminodiphenylmethane, phenylenediamine, or 2, 2-bis [4- (4-aminophenoxy) phenyl ] propane.

The resin particles according to the present invention preferably have a chemical structure derived from a polyfunctional epoxy resin and a chemical structure derived from a diamine compound, from the viewpoint that an exothermic peak can be more easily controlled and observed when the resin particles are heated from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min in an atmospheric atmosphere and differential scanning calorimetry is performed. For the same reason, the resin particles according to the present invention are preferably particles obtained by reacting a polyfunctional epoxy resin with a diamine compound. By heating a polyfunctional epoxy resin and a diamine compound in a solvent, an epoxy group and an amino group are sequentially reacted, and precipitates insoluble in the solvent are protected by a dispersion stabilizer while a granulation process is performed. In the granulation process, the granulation can be performed in a state where unreacted epoxy groups and amino groups remain in the particles and on the particle surface by adjusting conditions such as temperature and concentration at which the epoxy groups and amino groups react. The residual epoxy group and amino group were reacted by heating, and the heat of reaction was observed as an exothermic peak.

The acid anhydride curing agent is not particularly limited, and any acid anhydride can be widely used as long as it is used as a curing agent for a thermosetting compound such as an epoxy compound. Examples of the acid anhydride curing agent include bifunctional acid anhydride curing agents such as phthalic anhydride, tetrahydrophthalic anhydride, trialkyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylbutenyl-tetrahydrophthalic anhydride, phthalic acid derivative anhydrides, maleic anhydride, nadic anhydride, methylnadic anhydride, glutaric anhydride, succinic anhydride, glycerin dianhydride trimellitate, ethylene glycol dianhydride trimellitic acid, trifunctional acid anhydride curing agents such as trimellitic anhydride, and tetrafunctional or higher acid anhydride curing agents such as pyromellitic anhydride, benzophenone tetracarboxylic anhydride, methylcyclohexyl tetracarboxylic anhydride, and polyazelaic anhydride.

When the resin particles are obtained by polymerizing a polymerizable monomer having an ethylenically unsaturated group, examples of the polymerizable monomer having an ethylenically unsaturated group include a non-crosslinkable monomer and a crosslinkable monomer.

Examples of the non-crosslinkable monomer include styrene monomers such as styrene, α -methylstyrene and chlorostyrene as vinyl compounds; vinyl ether compounds such as methyl vinyl ether, ethyl vinyl ether and propyl vinyl ether; vinyl acid ester compounds such as vinyl acetate, vinyl butyrate, vinyl laurate and vinyl stearate; halogen-containing monomers such as vinyl chloride and vinyl fluoride; alkyl (meth) acrylate compounds such as methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, and isobornyl (meth) acrylate; oxygen atom-containing (meth) acrylate compounds such as hydroxyethyl 2- (meth) acrylate, glycerol (meth) acrylate, polyoxyethylene (meth) acrylate, and glycidyl (meth) acrylate; nitrile-containing monomers such as (meth) acrylonitrile; halogen-containing (meth) acrylates such as trifluoromethyl (meth) acrylate and pentafluoroethyl (meth) acrylate; olefin compounds such as diisobutylene, isobutylene, linear olefins, ethylene, propylene, etc. as α -olefin compounds; isoprene, butadiene, and the like as the conjugated diene compound.

Examples of the crosslinkable monomer include vinyl monomers such as divinylbenzene, 1, 4-dioxybutane and divinylsulfone as vinyl compounds; tetramethylolmethane tetra (meth) acrylate, polytetramethyleneol diacrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate, glycerol tri (meth) acrylate, polyfunctional (meth) acrylate compounds such as glycerol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polytetramethylene alcohol di (meth) acrylate, 1, 3-butanediol di (meth) acrylate, 1, 4-butanediol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, 1, 9-nonanediol di (meth) acrylate, and the like as the (meth) acrylic acid compounds; triallyl (iso) cyanurate, triallyl propionate, diallyl phthalate, diallyl acrylamide, diallyl ether as allyl compounds; silane alkoxide compounds such as tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, isopropyltrimethoxysilane, isobutyltrimethoxysilane, cyclohexyltrimethoxysilane, n-hexyltrimethoxysilane, n-octyltrimethoxysilane, n-decyltrimethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diisopropyldimethoxysilane, trimethoxysilylstyrene, gamma- (meth) acryloyloxypropyltrimethoxysilane, 1, 3-divinyltetramethyldisiloxane, methylphenyldimethoxysilane, and diphenyldimethoxysilane; vinyltrimethoxysilane, vinyltriethoxysilane, dimethoxymethylvinylsilane, dimethoxyethylvinylsilane, diethoxymethylvinylsilane, diethoxyethylvinylsilane, ethylmethyldiethylsilane, methylvinyldimethoxysilane, ethylvinyldimethoxysilane, silanolates containing a polymerizable double bond such as methylvinyldiethoxysilane, ethylvinyldiethoxysilane, p-vinyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyltriethoxysilane, and 3-acryloxypropyltrimethoxysilane; cyclic siloxanes such as decamethylcyclopentasiloxane; modified (reactive) silicone oils such as single-end modified silicone oils, double-end modified silicone oils, and side-chain silicone oils; carboxyl group-containing monomers such as (meth) acrylic acid, maleic acid, and maleic anhydride.

The resin particles can be obtained by polymerizing the polymerizable monomer having an ethylenically unsaturated group. The polymerization method is not particularly limited, and known methods such as radical polymerization, ionic polymerization, polycondensation (condensation polymerization ), addition polymerization, living polymerization, and living radical polymerization can be mentioned. Further, as another polymerization method, suspension polymerization in an environment in which a radical polymerization initiator is present can be cited.

The resin particles may be core-shell particles including a core and a shell disposed on a surface of the core. The shell preferably has a chemical structure derived from the polyfunctional epoxy resin and a chemical structure derived from the diamine compound, from the viewpoint that an exothermic peak can be more easily controlled and observed when differential scanning calorimetry is performed by heating the resin particles from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min in an atmospheric atmosphere. Further, for the same reason, the shell is preferably a shell obtained by reacting a polyfunctional epoxy resin with a diamine compound. As the material of the shell, the same material as that preferable for the resin particles can be used. The core may have a chemical structure derived from a polyfunctional epoxy resin and a chemical structure derived from a diamine compound, and may be a particle obtained by reacting a polyfunctional epoxy resin with a diamine compound.

The particle diameter of the resin particles is preferably 0.1 μm or more, more preferably 1 μm or more, and preferably 100 μm or less, more preferably 80 μm or less. When the particle diameter of the resin particles is not less than the lower limit and not more than the upper limit, the resin particles can be more preferably used for conductive particles and spacers. From the viewpoint of use as a spacer, the particle diameter of the resin particles is preferably 1 μm or more and 80 μm or less. From the viewpoint of use as conductive particles, the average particle diameter of the resin particles is preferably 1 μm or more and 20 μm or less.

The particle diameter of the resin particle is a diameter when the resin particle is in a true sphere shape, and when the resin particle is in a shape other than a true sphere shape, the particle diameter is a diameter when the particle is assumed to be in a true sphere shape corresponding to a volume of the particle. The particle diameter of the resin particles is preferably an average particle diameter, and more preferably a number average particle diameter. The particle diameter of the resin particles can be measured by an arbitrary particle size distribution measuring apparatus. For example, a particle size measurement distribution device to which the principles of laser light scattering, resistance value change, image analysis after imaging, and the like are applied can be used. More specifically, as a method for measuring the particle diameter of the resin particles, there is a method of measuring the particle diameters of about 100000 resin particles by using a particle size distribution measuring apparatus ("Multisizer 4" manufactured by Beckman coulter corporation) and calculating the average value thereof.

The coefficient of variation (CV value) in the particle diameter of the resin particles is preferably 10% or less, more preferably 7% or less, and still more preferably 5% or less. When the CV value is not more than the upper limit, the resin particles can be more preferably used for conductive particles and spacers.

The CV value is represented by the following formula.

CV value (%) - (ρ/Dn) × 100

ρ standard deviation of particle diameter of resin particle

Dn is the average value of particle diameters of resin particles

The aspect ratio of the resin particles is preferably 2 or less, more preferably 1.5 or less, and still more preferably 1.2 or less. The aspect ratio is a major axis/minor axis. The aspect ratio is preferably determined by observing arbitrary 10 resin particles under an electron microscope or an optical microscope, and calculating the average of the major axis and the minor axis of each resin particle by setting the maximum diameter and the minimum diameter to the major axis and the minor axis, respectively.

(conductive particles)

The conductive particles include the resin particles and a conductive portion disposed on a surface of the resin particles.

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

The conductive particle 1 shown in fig. 1 includes a resin particle 11 and a conductive portion 2 disposed on the surface of the resin particle 11. The conductive part 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.

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

The conductive particles 21 shown in fig. 2 include resin particles 11 and conductive portions 22 disposed on the surfaces of the resin particles 11. In the conductive particle 21 shown in fig. 2, only the conductive portion 22 is different from the conductive particle 1 shown in fig. 1. Conductive portion 22 includes first conductive portion 22A as an inner layer and second conductive portion 22B as an outer layer. First conductive portion 22A is disposed on the surface of resin particle 11. Second conductive portion 22B is disposed on the surface of first conductive portion 22A.

Fig. 3 is a cross-sectional view showing conductive particles according to a third embodiment of the present invention.

The conductive particles 31 shown in fig. 3 include resin particles 11, conductive portions 32, a plurality of core materials 33, and a plurality of insulating materials 34.

The conductive portion 32 is disposed on the surface of the resin particle 11. The conductive particles 31 have a plurality of protrusions 31a on the conductive surface. The conductive portion 32 has a plurality of protrusions 32a on an outer surface. Thus, the conductive particles may have protrusions on the conductive surface of the conductive particles, or may have protrusions on the outer surface of the conductive portion. The plurality of core materials 33 are disposed on the surface of the resin particle 11. The plurality of core materials 33 are embedded in the conductive portion 32. The core material 33 is disposed inside the protrusions 31a, 32 a. The conductive portion 32 covers the plurality of core materials 33. The outer surface of the conductive portion 32 is raised by the plurality of core materials 33, thereby forming protrusions 31a, 32 a.

The conductive particles 31 have an insulating material 34 disposed on the outer surface of the conductive portion 32. At least a part of the outer surface of the conductive portion 32 is covered with an insulating material 34. The insulating material 34 is made of an insulating material, and is insulating particles. Thus, the conductive particles may have an insulating material disposed on the outer surface of the conductive portion.

The metal used 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, tungsten, molybdenum, and alloys thereof. Further, as the metal, tin-doped indium oxide (ITO), solder, and the like can be cited. From the viewpoint of further improving the reliability of the inter-electrode connection, the metal is preferably an alloy containing tin, nickel, palladium, copper, or gold, and more preferably nickel or palladium.

As shown in the conductive particles 1 and 31, the conductive portion may be formed of one layer. As shown by the conductive particles 21, the conductive portion may be formed of 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 more preferably a gold layer. When the outermost layer is these preferable conductive layers, the connection reliability between the electrodes can be further improved. In addition, when the outermost layer is a gold layer, the corrosion resistance can be further improved.

The method for forming the conductive portion on the surface of the resin particle is not particularly limited. Examples of the method for forming the conductive portion include a method of electroless plating, a method of plating, a physical vapor deposition method, and a method of applying a paste containing a metal powder or a metal powder and a binder to the surface of the resin particle. From the viewpoint of further facilitating the formation of the conductive portion, it is preferable to use an electroless plating method. Examples of the physical vapor deposition method include vacuum vapor deposition, ion plating, and ion sputtering.

The compression elastic modulus when the conductive particles are compressed by 10% is set as 10% K value (C). The compression elastic modulus of the conductive particles after heating at 200 ℃ for 10 minutes at 10% compression is set as 10% K value (D). The absolute value of the difference between the 10% K value (C) and the 10% K value (D) is preferably 180N/mm²Above, more preferably 500N/mm²Above, more preferably 800N/mm²Above, 1000N/mm is particularly preferable²The above. The absolute value of the difference between the 10% K value (C) and the 10% K value (D) is preferably 10000N/mm²More preferably 7500N/mm²The concentration is preferably 5000N/mm or less²The following. When the absolute value of the difference between the 10% K value (C) and the 10% K value (D) is not less than the lower limit and not more than the upper limit, the adhesion and impact resistance of the conductive part can be further effectively improved when the electrodes are electrically connected, and the continuous connection can be further effectively reducedAnd (6) connecting a resistor. The absolute value of the difference between the 10% K value (C) and the 10% K value (D) is particularly preferably 200N/mm²Above 3000N/mm²The following. When the absolute value of the difference between the 10% K value (C) and the 10% K value (D) satisfies the preferable range, scratches of the adherend caused by the conductive particles can be further effectively suppressed, and the conductive particles can be further uniformly brought into contact with the adherend. If the absolute value of the difference between the 10% K value (C) and the 10% K value (D) satisfies the preferable range, the connection resistance can be further effectively reduced and the connection reliability can be further effectively improved when the electrodes are electrically connected.

The above 10% K value (C) is preferably 3000N/mm²Above, more preferably 4000N/mm²Above, and preferably 11000N/mm²Below, 9000N/mm is more preferable²The following. When the 10% K value (C) is not less than the lower limit and not more than the upper limit, scratches of the adherend by the conductive particles can be more effectively suppressed, and the conductive particles can be more uniformly brought into contact with the adherend. When the 10% K value (C) is not less than the lower limit and not more than the upper limit, the connection resistance can be more effectively reduced and the connection reliability can be more effectively improved when the electrodes are electrically connected.

The compressive modulus of elasticity (the 10% K value (C) and the 10% K value (D)) of the conductive particles can be measured in the following manner.

Conductive particles (C)) are prepared. Further, conductive particles (D)) heated at 200 ℃ for 10 minutes were prepared. A conductive particle (C) or (D) was compressed on a smooth indenter end face of a cylinder (50 μm in diameter, made of diamond) at 25 ℃ at a compression speed of 0.3 mN/sec and a maximum test load of 20mN using a micro compression tester. The load value (N) and the compression displacement (mm) at this time were measured. The compression modulus (10% K value (C) or 10% K value (D)) can be obtained from the obtained measurement values according to the following formula. As the micro compression tester, for example, Fisherscope H-100 manufactured by Fisher corporation, and the like can be used. The modulus of elasticity (10% K value (C) or 10% K value (D)) of the conductive particles (C) or (D) is preferably calculated by arithmetically averaging the modulus of elasticity (10% K value (C) or 10% K value (D)) of the compression of 50 arbitrarily selected conductive particles (C) or (D).

10% K value (C) or 10% K value (D) (N/mm)²)＝(3/2^1/2)·F·S^-3/2·R^-1/2

F: load value (N) after 10% compression deformation of conductive particles (C) or (D)

S: compression displacement (mm) after 10% compression deformation of the conductive particles (C) or (D)

R: radius (mm) of conductive particle (C) or (D)

The compressive modulus of elasticity generally and quantitatively represents the hardness of the conductive particles. By using the above-described compressive modulus of elasticity, the hardness of the conductive particles can be quantitatively and uniquely expressed.

The conductive particles preferably have a compression recovery rate of 5% or more, more preferably 8% or more, and preferably 60% or less, more preferably 40% or less. When the compression recovery rate is not less than the lower limit and not more than the upper limit, the occurrence of scratches on the adherend by the conductive particles can be more effectively suppressed, and the conductive particles can be more uniformly brought into contact with the adherend. When the compression recovery ratio is not less than the lower limit and not more than the upper limit, the connection resistance between the electrodes can be further effectively reduced and the connection reliability can be further effectively improved when the electrodes are electrically connected.

The compression recovery rate of the conductive particles can be measured as follows.

Conductive particles are scattered on the sample stage. Using a micro compression tester, a load (reverse load value) was applied to 1 scattered conductive particle in the center direction of the conductive particle by a micro compression tester at 25 ℃ on the smooth indenter end face of a cylinder (diameter 50 μm, made of diamond) until the conductive particle was compressively deformed by 30%. Subsequently, the load was taken up to the initial load value (0.4 mN). The load-compression displacement in the above process is measured, and the compression recovery rate can be obtained according to the following equation. The load speed was set to 0.33 mN/second. As the micro compression tester, for example, Fisherscope H-100 manufactured by Fisher corporation, and the like can be used.

Compression recovery rate (%) [ L2/L1] x 100

L1: compression displacement from a load value at origin to a reverse load value when a load is applied

L2: unload displacement from reverse load value at load release to load value for origin

The particle diameter of the conductive particles is preferably 0.5 μm or more, more preferably 1.0 μm or more, and preferably 500 μm or less, more preferably 450 μm or less, still more preferably 100 μm or less, further preferably 50 μm or less, and particularly preferably 20 μm or less. When the particle diameter of the conductive particles is not less than the lower limit and not more than the upper limit, the contact area between the conductive particles and the electrodes is sufficiently increased when the electrodes are connected using the conductive particles, and the aggregated conductive particles are not easily formed when the conductive portion is formed. Further, the distance between electrodes connected via the conductive particles does not become excessively large, and the conductive portion is not easily peeled off from the surface of the resin particle. When the particle diameter of the conductive particles is not less than the lower limit and not more than the upper limit, the conductive particles can be preferably used for the use of a conductive material.

The particle diameter of the conductive particles is a diameter when the conductive particles are in a true sphere shape, and when the conductive particles are in a shape other than a true sphere shape, the particle diameter is assumed to be in a true sphere shape corresponding to the volume of the conductive particles.

The particle diameter of the conductive particles is preferably an average particle diameter, and more preferably a number average particle diameter. The particle diameter of the conductive particles can be determined by observing arbitrary 50 conductive particles under an electron microscope or an optical microscope and calculating an average value, or by performing laser diffraction type particle size distribution measurement. The particle diameter of each conductive particle is determined as a circle-equivalent diameter particle diameter in observation under an electron microscope or an optical microscope. When observed with an electron microscope or an optical microscope, the average particle diameter of the circle-equivalent diameter of arbitrary 50 conductive particles is almost the same as the average particle diameter of the sphere-equivalent diameter. In the laser diffraction particle size distribution measurement, the particle diameter of each conductive particle is determined as the particle diameter of the spherical equivalent diameter. The particle diameter of the conductive particles is preferably calculated by a laser diffraction particle size distribution measurement method.

The thickness of the conductive portion is preferably 0.005 μm or more, more preferably 0.01 μm or more, and preferably 10 μm or less, more preferably 1 μm or less, and further preferably 0.3 μm or less. If the conductive portion is a multilayer, the thickness of the conductive portion is the thickness of the entire conductive portion. When the thickness of the conductive portion is not less than the lower limit and not more than the upper limit, sufficient conductivity can be obtained without causing the conductive particles to be excessively hard, and the conductive particles are sufficiently deformed when the electrodes are connected.

When the conductive portion is formed of a plurality of layers, the thickness of the conductive portion in the outermost layer is preferably 0.001 μm or more, more preferably 0.01 μm or more, and preferably 0.5 μm or less, more preferably 0.1 μm or less. When the thickness of the outermost conductive part is not less than the lower limit and not more than the upper limit, the coating by the outermost conductive part becomes uniform, the corrosion resistance becomes sufficiently high, and the connection reliability between the electrodes can be further improved. In addition, when the outermost layer is a gold layer, the thinner the thickness of the gold layer is, the lower the cost is.

The thickness of the conductive portion can be measured by observing the cross section of the conductive particle using, for example, a Transmission Electron Microscope (TEM). The thickness of the conductive portion is preferably calculated by taking the average value of the thicknesses of any of the conductive portions at 5 points as the thickness of the conductive portion of one conductive particle, and more preferably calculated by taking the average value of the entire thicknesses of the conductive portions as the thickness of the conductive portion of one conductive particle. The thickness of the conductive portion is preferably determined by calculating an average value of the conductive portion thicknesses of the respective 20 arbitrary conductive particles.

The conductive particles preferably have protrusions on the outer surface of the conductive portion. The conductive particles preferably have protrusions on the conductive surface. The projection is preferably a plurality of projections. Oxide films are often formed on the surfaces of the conductive portions and the surfaces of the electrodes connected by the conductive particles. When the conductive particles having the protrusions are used, the oxide film is effectively removed by the protrusions by disposing the conductive particles between the electrodes and pressure-bonding the conductive particles. Therefore, the electrode can be brought into contact with the conductive portion of the conductive particle more reliably, and the connection resistance between the electrodes can be further reduced. Further, when the conductive particles have an insulating material on the surface thereof, or when the conductive particles are dispersed in a binder resin and used as a conductive material, the insulating material or the binder resin between the conductive particles and the electrode can be removed more effectively due to the protrusions of the conductive material. Therefore, the reliability of the connection between the electrodes can be further improved.

As a method for forming the protrusions on the surface of the conductive particles, there can be mentioned a method in which a core material is attached to the surface of a resin particle, and then a conductive portion is formed by electroless plating; and a method of forming the conductive portion by electroless plating on the surface of the resin particle, then attaching the core material, and further forming the conductive portion by electroless plating, and the like. In addition, the core material may not be used for forming the protrusions.

The method for forming the protrusion may be as follows. A method of adding a core material to the surface of the resin particle at an intermediate stage of forming the conductive portion by electroless plating. As a method of forming the protrusions by electroless plating without using a core material, there is a method of generating metal nuclei by electroless plating, attaching the metal nuclei to the surface of the resin particles or the conductive portions, and further forming the conductive portions by electroless plating.

The conductive particles further preferably include an insulating material disposed on an outer surface of the conductive portion. In this case, when conductive particles are used to connect electrodes, short-circuiting between adjacent electrodes can be prevented. Specifically, when a plurality of conductive particles are brought into contact with each other, an insulating material is present between a plurality of electrodes, and therefore, short circuit is prevented from occurring between laterally adjacent electrodes, not between upper and lower electrodes. In addition, when the electrodes are connected, the insulating material between the conductive portion of the conductive particle and the electrode can be easily removed by pressurizing the conductive particle using two electrodes. When the conductive particles have protrusions on the surface of the conductive portion, the insulating material between the conductive portion of the conductive particles and the electrode can be further easily removed. The insulating material is preferably an insulating resin layer or insulating particles, and more preferably insulating particles. The insulating particles are preferably insulating resin particles.

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

(conductive Material)

The conductive material contains the conductive particles and a binder resin. The conductive particles are preferably dispersed in a binder resin and used as a conductive material. The conductive material is preferably an anisotropic conductive material. The above-mentioned conductive material is preferably used for electrical connection of the electrodes. The conductive material is preferably a circuit connecting material.

The binder resin is not particularly limited. As the adhesive resin, a known insulating resin can be used. The adhesive resin 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 adhesive resin include vinyl resins, thermoplastic resins, curable resins, thermoplastic block copolymers, and elastomers. The adhesive resin may be used alone or in combination of two or more.

Examples of the vinyl resin include vinyl acetate resin, acrylic resin, and styrene resin. Examples of the thermoplastic resin include polyolefin resins, ethylene-vinyl acetate copolymers, and polyamide resins. Examples of the curable resin include epoxy resins, polyurethane resins, polyimide resins, and unsaturated polyester resins. 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 a styrene-butadiene-styrene block copolymer, a styrene-isoprene-styrene block copolymer, a hydrogenated product of a styrene-butadiene-styrene block copolymer, and a hydrogenated product of a styrene-isoprene-styrene block copolymer. Examples of the elastomer include styrene-butadiene copolymer rubber and acrylonitrile-styrene block copolymer rubber.

The conductive material may contain various additives such as a filler, an extender, a softener, a plasticizer, a polymerization catalyst, a curing catalyst, a colorant, an antioxidant, a heat stabilizer, a light stabilizer, an ultraviolet absorber, a lubricant, an antistatic agent, and a flame retardant in addition to the conductive particles and the binder resin.

The method for dispersing the conductive particles in the binder resin may be a conventionally known method, and is not particularly limited. As a method of dispersing the conductive particles in the binder resin, for example, the following method can be mentioned. A method of adding the conductive particles to the adhesive resin, and then kneading and dispersing the mixture using a planetary mixer or the like. A method in which the conductive particles are uniformly dispersed in water or an organic solvent using a homogenizer or the like, then added to the binder resin, and kneaded and dispersed using a planetary mixer or the like. A method of diluting the binder resin with water, an organic solvent, or the like, adding the conductive particles, and kneading and dispersing the mixture using a planetary mixer or the like.

The viscosity (η 25) of the conductive material at 25 ℃ is preferably 30Pa · s or more, more preferably 50Pa · s or more, and is preferably 400Pa · s or less, more preferably 300Pa · s or less. When the viscosity of the conductive material at 25 ℃ is not lower than the lower limit and not higher than the upper limit, the connection reliability between electrodes can be further effectively improved. The viscosity (. eta.25) can be suitably adjusted by the kind and the amount of the compounding ingredients.

For example, the viscosity (. eta.25) can be measured at 25 ℃ and 5rpm using an E-type viscometer ("TVE 22L", manufactured by Toyobo industries, Ltd.).

The conductive material can be used as a conductive paste, a conductive film, or the like. When the conductive material according to the present invention is a conductive film, a film containing no conductive particles may be stacked on the conductive film containing conductive particles. The conductive paste is preferably an anisotropic conductive paste. The conductive film is preferably an anisotropic conductive film.

The content of the binder resin 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 99.99% by weight or less, more preferably 99.9% by weight or less, in 100% by weight of the conductive material. When the content of the binder resin is not less than the lower limit and not more than the upper limit, the conductive particles are efficiently arranged between the electrodes, and the connection reliability of the connection target members connected by the conductive material is further improved.

The content of the conductive particles is preferably 0.01 wt% or more, more preferably 0.1 wt% or more, and preferably 80 wt% or less, more preferably 60 wt% or less, even more preferably 40 wt% or less, even more preferably 20 wt% or less, and particularly preferably 10 wt% or less, in 100 wt% of the conductive material. When the content of the conductive particles is not less than the lower limit and not more than the upper limit, the connection resistance between the electrodes can be further reduced, and the connection reliability between the electrodes can be further improved.

(connection structure)

The connection structure can be obtained by connecting members to be connected by using a conductive material containing the conductive particles or the conductive particles and a binder resin.

The connection structure includes: the first connection object member has a first electrode on a surface thereof, the second connection object member has a second electrode on a surface thereof, and the connection portion connects the first connection object member and the second connection object member together. In the connection structure, the connection portion is formed of conductive particles or a conductive material containing the conductive particles and a binder resin. The conductive particles include the resin particles and a conductive portion disposed on a surface of the resin particles. In the connection structure, the first electrode and the second electrode are electrically connected by the conductive particles.

When the conductive particles are used alone, the connection portion itself is a conductive particle. That is, the first member to be connected and the second member to be connected are electrically connected by the conductive particles. The conductive material for obtaining the connection structure is preferably an anisotropic conductive material.

Fig. 4 is a cross-sectional view showing an example of a connection structure using conductive particles according to the first embodiment of the present invention.

The connection structure 41 shown in fig. 4 includes a first connection target member 42, a second connection target member 43, and a connection portion 44 that connects the first connection target member 42 and the second connection target member 43 together. The connection portion 44 is formed of a conductive material containing the conductive particles 1 and a binder resin. In fig. 4, the conductive particles 1 are schematically illustrated for convenience of illustration. The conductive particles 21 and 31 may be used instead of the conductive particles 1.

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

The method for producing the connection structure is not particularly limited. As an example of a method for manufacturing a connection structure, there is a method in which the above-described conductive material is disposed between a first connection target member and a second connection target member to obtain a laminated body, and then the laminated body is heated and pressed. The pressure at the time of pressurization is preferably 40MPa or more, more preferably 60MPa or more, and preferably 90MPa or less, more preferably 70MPa or less. The temperature at the time of heating is preferably 80 ℃ or higher, more preferably 100 ℃ or higher, and preferably 140 ℃ or lower, more preferably 120 ℃ or lower.

The first connection object member and the second connection object member are not particularly limited. Specific examples of the first connection object member and the second connection object member include electronic components such as semiconductor chips, semiconductor packages, LED chips, LED packages, capacitors, and diodes, and electronic components such as resin films, printed circuit boards, flexible flat cables, rigid flexible boards, glass epoxy boards, and circuit boards such as glass boards. The first connection object component and the second connection object component are preferably electronic components.

The conductive material is preferably a conductive material for connecting electronic components. The conductive paste is preferably 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 connecting material are preferably used for a touch panel. Therefore, the connection target member is preferably a flexible substrate or a connection target member in which an electrode is disposed on a surface of a resin film. The member to be connected is preferably a flexible substrate, and is preferably a member to be connected in which an electrode is disposed on a surface of a resin film. When the flexible substrate is a flexible printed substrate or the like, the flexible substrate usually has an electrode on its surface.

Examples of the electrode provided on the connection target member include metal electrodes such as a gold electrode, a nickel electrode, a tin electrode, an aluminum electrode, a copper electrode, a molybdenum electrode, a silver electrode, an SUS 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, a silver 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. In addition, when the electrode is an aluminum electrode, the electrode may be an electrode formed of only aluminum, or 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, zinc oxide doped with a trivalent metal element, and the like. The trivalent metal element includes Sn, Al, Ga, and the like.

Further, the above resin particles can be preferably used as a spacer for a liquid crystal display element. The first connection target member may be a member for a first liquid crystal display element. The second connection target member may be a second liquid crystal display element member. The connection portion may be a seal portion that seals the peripheries of the first liquid crystal display element member and the 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.

The resin particles can be used for a periphery sealing agent for a liquid crystal display element. The liquid crystal display element includes a first liquid crystal display element member and a second liquid crystal display element member. The liquid crystal display element further includes: a sealing portion for sealing the peripheries of the first liquid crystal display element member and the 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, and a liquid crystal disposed between the first liquid crystal display element member and the second liquid crystal display element member. In this liquid crystal display element, a liquid crystal dropping method is employed, and the sealing portion is formed by thermally curing a sealant for the liquid crystal dropping method.

1mm in the above liquid crystal display element²The arrangement density of the corresponding spacers for liquid crystal display element is preferably 10 pieces/mm²Above, and preferably 1000/mm²The following. If the arrangement density is 10 pieces/mm²In this way, the cell gap becomes more uniform. If the arrangement density is 1000 pieces/mm²The contrast of the liquid crystal display element is further improved as follows.

(electronic parts device)

The resin particles or the conductive particles are disposed between the first ceramic member and the second ceramic member in the outer peripheral portions of the first ceramic member and the second ceramic member, and can be used as a gap control material and a conductive connecting material.

Fig. 5 is a cross-sectional view showing an example of an electronic component device using the resin particles according to the present invention. Fig. 6 is an enlarged sectional view of a joint portion in the electronic component device shown in fig. 5.

The electronic component device 81 shown in fig. 5 and 6 includes a first ceramic member 82, a second ceramic member 83, a bonding portion 84, an electronic component 85, and a lead frame 86.

The first ceramic member 82 and the second ceramic member 83 are each formed of a ceramic material. For example, the first and second ceramic members 82 and 83 are casings, respectively. The first ceramic member 82 is, for example, a substrate. The second ceramic member 83 is, for example, a lid. The first ceramic member 82 has a convex portion protruding toward (above) the second ceramic member 83 on the outer peripheral portion. The first ceramic member 82 has a recess portion forming an internal space R for accommodating the electronic component 85 on the second ceramic member 83 side (upper side). Note that the first ceramic member 82 may not have a convex portion. The second ceramic member 83 has a convex portion protruding toward the first ceramic member 82 (lower side) on the outer peripheral portion. The second ceramic member 83 has a recess portion forming an internal space R for accommodating the electronic component 85 on the first ceramic member 82 side (lower side). Note that the second ceramic member 83 may not have a convex portion. The internal space R is formed by the first ceramic member 82 and the second ceramic member 83.

The joint portion 84 joins the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83 together. Specifically, the joint portion 84 joins a convex portion of the outer peripheral portion of the first ceramic member 82 and a convex portion of the outer peripheral portion of the second ceramic member 83.

The package is formed of a first ceramic member 82 and a second ceramic member 83 joined by a joining portion 84. The inner space R is formed by the package. The joint 84 seals the internal space R liquid-tightly and gas-tightly. The joint portion 84 is a seal portion.

The electronic component 85 is disposed in the internal space R of the package. Specifically, the electronic component 85 is disposed on the first ceramic component 82. In the present embodiment, two electronic components 85 are used.

The joint 84 includes a plurality of resin particles 11 and glass 84B. The bonding portion 84 is formed using a bonding material containing a plurality of resin particles 11 different from the glass particles and glass 84B. The bonding material is a bonding material for ceramic package. The bonding material may contain the conductive particles described above in place of the resin particles.

The bonding material may contain a solvent or a resin. In the joint portion 84, glass 84B such as glass particles is melted, bonded, and then solidified.

Examples of the electronic component include a sensor element, a MEMS, and a die. Examples of the sensor element include a pressure sensor element, an acceleration sensor element, a CMOS sensor element, a CCD sensor element, and a housing of the various sensor elements.

The lead frame 86 is disposed between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83. The lead frame 86 extends toward the inner space R side and the outer space side of the package. The terminals of the electronic component 85 and the lead frame 86 are electrically connected by wires.

The joint portion 84 partially directly joins the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83, and partially indirectly joins the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83. Specifically, the joint portion 84 indirectly joins the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83 together via the lead frame 86 in a portion having the lead frame 86 between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83. In a portion having the lead frame 86 between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83, the first ceramic member 82 is in contact with the lead frame 86, and the lead frame 86 is in contact with the first ceramic member 82 and the joint portion 84. Further, the bonding portion 84 is in contact with the lead frame 86 and the second ceramic member 83, and the second ceramic member 83 is in contact with the bonding portion 84. The joint portion 84 directly joins the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83 together in a portion between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83, which portion does not have the lead frame 86. In a portion between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83 where the lead frame 86 is not provided, the joint portion 84 makes the first ceramic member 82 contact with the second ceramic member 83.

In a portion having the lead frame 86 between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83, the distance of the gap between the outer peripheral portion of the first ceramic member 82 and the outer peripheral portion of the second ceramic member 83 is controlled by the plurality of resin particles 11 contained in the joint portion 84.

The joint portion may be formed by directly or indirectly joining the outer peripheral portion of the first ceramic member and the outer peripheral portion of the second ceramic member. An electrical connection method other than the lead frame may be employed.

As shown in the electronic component device 81, the electronic component device may include, for example: the ceramic electronic component includes a first ceramic component formed of a ceramic material, a second ceramic component formed of a ceramic material, a joint portion, and an electronic component. In the electronic component device, the joining portion may join an outer peripheral portion of the first ceramic member and an outer peripheral portion of the second ceramic member directly or indirectly. In the electronic component device, a package may be formed by the first ceramic member and the second ceramic member joined by the joining portion. In the electronic component device, the electronic component may be disposed in an internal space of the package, and the bonding portion may include a plurality of resin particles and glass.

As shown in the bonding material used in the electronic component device 81, the bonding material for ceramic sealing is used for forming the bonding portion in the electronic component device, and contains resin particles and glass. An electrical connection method including only resin particles and not glass may be employed. The bonding portion may contain the conductive particles in place of the resin particles.

Hereinafter, the present invention will be specifically described by way of examples and comparative examples. The present invention is not limited to the following examples.

(example 1)

(1) Preparation of resin particles

To a reaction vessel equipped with a thermometer, a stirrer and a cooling tube, 15 parts by weight of 2, 2-bis (4-glycidoxyphenyl) propane (manufactured by tokyo chemical industry co., ltd.), 7.5 parts by weight of polyvinylpyrrolidone as a dispersion stabilizer and 250 parts by weight of ethanol were charged, and the mixture was stirred at 65 ℃ for 1 hour to be uniformly dissolved. Subsequently, 4.37 parts by weight of 4, 4' -diaminodiphenylmethane and 35 parts by weight of ethanol were uniformly dissolved, and then placed in a reaction vessel to react at 65 ℃ for 24 hours, to obtain a reaction product. The obtained reaction product was washed and dried to obtain resin particles.

(2) Preparation of conductive particles

10 parts by weight of the obtained resin particles were dispersed in 100 parts by weight of an alkaline solution containing 5% by weight of a palladium catalyst solution using an ultrasonic disperser, and then the resin particles were taken out by filtering the solution. Subsequently, the resin particles were added to 100 parts by weight of a1 wt% dimethylamine borane solution to activate the surfaces of the resin particles. After the resin particles whose surfaces were activated were thoroughly washed with water, they were added to 500 parts by weight of distilled water and dispersed, thereby obtaining a dispersion liquid.

Further, a nickel plating solution (pH8.5) containing 0.35mol/L of nickel sulfate, 1.38mol/L of dimethylamine borane, and 0.5mol/L of sodium citrate was prepared.

The obtained dispersion was stirred at 60 ℃ and the nickel plating solution was gradually dropped into the dispersion to carry out electroless plating. Subsequently, the dispersion was filtered to remove the particles, washed with water, and dried to obtain conductive particles in which a nickel-boron conductive layer was formed on the surface of the resin particles and a conductive portion was provided on the surface.

(3) Preparation of electroconductive Material (Anisotropic electroconductive paste)

7 parts by weight of the conductive particles, 25 parts by weight of bisphenol A type phenoxy resin, 4 parts by weight of fluorene type epoxy resin, 30 parts by weight of phenol novolac type epoxy resin and SI-60L (Sanxin chemical Co., Ltd.) were mixed, and defoaming and stirring were performed for 3 minutes, thereby obtaining a conductive material (anisotropic conductive paste).

(4) Preparation of connection Structure

A transparent glass substrate (first connection object member) was prepared, on the upper surface of which an IZO electrode pattern (first electrode, metal on the electrode surface having a vickers hardness of 100Hv) having an L/S of 10 μm/10 μm was formed. Further, a semiconductor wafer (second connection object member) having an Au electrode pattern (second electrode, metal on the electrode surface having a Vickers hardness of 50Hv) with an L/S of 10 μm/10 μm formed on the lower surface thereof was prepared. The obtained anisotropic conductive paste was applied to the transparent glass substrate to a thickness of 30 μm, thereby forming an anisotropic conductive paste layer. Subsequently, the semiconductor chip is stacked on the anisotropic conductive paste layer so that the electrodes face each other. Thereafter, the temperature of the header was adjusted so that the temperature of the anisotropic conductive paste layer became 100 ℃, and a heating and pressurizing head was placed on the upper surface of the semiconductor wafer, and a pressure of 55MPa was applied to cure the anisotropic conductive paste layer at 100 ℃, thereby obtaining a connection structure.

(example 2)

In the preparation of the resin particles, a glycidylamine-type epoxy resin ("TETRAD-X" manufactured by mitsubishi gas chemical corporation) was used in place of 2, 2-bis (4-glycidoxyphenyl) propane, and isopropanol was used in place of ethanol. The amount of 4, 4' -diaminodiphenylmethane was adjusted from 4.37 parts by weight to 7.53 parts by weight. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except for the above modifications.

(example 3)

In the preparation of the resin particles, triazine type epoxy resin ("TEPIC-PAS" manufactured by Nissan chemical Co., Ltd.) was used in place of 2, 2-bis (4-glycidoxyphenyl) propane. In addition, 1.63 parts by weight of ethylenediamine was used instead of 4.37 parts by weight of 4, 4' -diaminodiphenylmethane. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except for the above modifications.

(example 4)

In the preparation of the resin particles, a glycidylamine-type epoxy resin ("JER-630" manufactured by Mitsubishi chemical corporation) was used in place of 2, 2-bis (4-glycidoxyphenyl) propane. The amount of 4, 4' -diaminodiphenylmethane was adjusted from 4.37 parts by weight to 7.63 parts by weight. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except for the above modification.

(example 5)

In the production of the resin particles, an alicyclic glycidylamine-type epoxy resin ("TETRAD-C" manufactured by mitsubishi gas chemical corporation) was used in place of 2, 2-bis (4-glycidoxyphenyl) propane, and isopropanol was used in place of ethanol. The amount of 4, 4' -diaminodiphenylmethane was adjusted from 4.37 parts by weight to 7.44 parts by weight. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except for the above modifications.

(example 6)

In the preparation of the resin particles, 1g of nickel particle slurry (average particle diameter 100nm) was added to the dispersion for 3 minutes to obtain a suspension containing the resin particles to which the core material was attached. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except that the above suspension was used instead of the above dispersion liquid.

(example 7)

(1) Preparation of insulating particles

A1000 mL separating flask equipped with a four-port separable cap, a stirring blade, a three-way cock, a cooling tube, and a temperature probe was charged with the following monomer composition, and then distilled water was added thereto so that the solid content of the following monomer composition became 10% by weight, and the mixture was stirred at 200rpm and polymerized at 60 ℃ for 24 hours under a nitrogen atmosphere. The monomer composition contained 360mmol of methyl methacrylate, 45mmol of glycidyl methacrylate, 20mmol of p-styryldiethylphosphine, 13mmol of ethylene glycol dimethacrylate, 0.5mmol of polyvinylpyrrolidone and 1mmol of 2, 2' -azobis {2- [ N- (2-carboxyethyl) amidino ] propane }. After the reaction, the reaction mixture was freeze-dried to obtain insulating particles (particle size: 360nm) having phosphorus atoms derived from p-diethylphosphine on the surface.

(2) Preparation of conductive particles with insulating particles

Conductive particles obtained in example 6 were prepared. The insulating particles obtained above were dispersed in distilled water under ultrasonic irradiation to obtain a 10 wt% aqueous dispersion of the insulating particles. 10g of the prepared conductive particles were dispersed in 500mL of distilled water, and 1g of a 10 wt% aqueous dispersion of insulating particles was added thereto and stirred at room temperature for 8 hours. After filtering the mixture with a 3 μm mesh filter, the mixture was washed with methanol and dried to obtain conductive particles with insulating particles. A conductive material and a connection structure were obtained in the same manner as in example 1, except that the conductive particles with insulating particles were used instead of the conductive particles.

(example 8)

(1) Preparation of resin particles

Polystyrene particles having an average particle diameter of 0.93 μm were prepared as seed particles. 3.9 parts by weight of the above polystyrene particles, 500 parts by weight of ion-exchanged water, and 120 parts by weight of a 5% by weight aqueous polyvinyl alcohol solution were mixed to prepare a mixed solution. After the mixture was dispersed by ultrasonic waves, it was put into a separable flask and stirred until uniform.

Subsequently, the following monomer components, 2 parts by weight of 2, 2' -azobis (methyl isobutyrate) (manufactured by Wako pure chemical industries, Ltd. "V-601"), 2 parts by weight of benzoyl peroxide (manufactured by Niper BW, manufactured by Nikkiso Co., Ltd.) and 4 parts by weight of 2, 2-bis (4, 4-di-t-butylperoxycyclohexyl) propane (manufactured by Nikkiso Co., Ltd. "Pertetra A") were mixed. The monomer component contained 30 parts by weight of 1, 6-hexanediol dimethacrylate and 120 parts by weight of styrene. Further, 9 parts by weight of triethanolamine lauryl sulfate, 30 parts by weight of ethanol (solvent) and 1100 parts by weight of ion-exchanged water were added to prepare an emulsion.

The emulsion was added to the mixture in a separable flask in several portions, and stirred for 12 hours to allow the particles to absorb the monomer, thereby obtaining a suspension containing monomer-swollen particles.

Subsequently, 490 parts by weight of a 5% by weight aqueous polyvinyl alcohol solution was added, heating was started and the reaction was carried out at 85 ℃ for 9 hours, to obtain resin particles.

Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except that the obtained resin particles were used.

(example 9)

Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 8, except that, in the preparation of the resin particles, 75 parts by weight of hexylethyl methacrylate and 75 parts by weight of glycidyl methacrylate were used instead of 30 parts by weight of 1, 6-hexanediol dimethacrylate and 120 parts by weight of styrene.

(example 10)

Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 8, except that 150 parts by weight of 1, 3-butanediol dimethacrylate was used instead of 30 parts by weight of 1, 6-hexanediol dimethacrylate and 120 parts by weight of styrene in the preparation of the resin particles.

(example 11)

In the preparation of the resin particles, 2.34 parts by weight of 1, 4-phenylenediamine was used instead of 4.37 parts by weight of 4, 4' -diaminodiphenylmethane. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except for the above modifications.

(example 12)

In the preparation of the resin particles, 8.90 parts by weight of 2, 2-bis [4- (4-aminophenoxy) phenyl ] propane was used instead of 4.37 parts by weight of 4, 4' -diaminodiphenylmethane. Resin particles, conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except for the above modifications.

Comparative example 1

"Optobeads 3500M" (melamine-based resin, particle diameter: 3.5 μ M) manufactured by Nissan chemical Co., Ltd was prepared as resin particles. Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except that the prepared resin particles were used.

(example 13)

To a reaction vessel equipped with a thermometer, a stirrer and a cooling tube, 50 parts by weight of "Micropearl SP 210" (a (meth) acrylic resin having a particle diameter of 10 μm) as a base core resin particle, 500 parts by weight of water and 125 parts by weight of polyallylamine as a dispersion stabilizer were charged and uniformly mixed, and then reacted at 25 ℃ for 1 hour to obtain a reaction product. The obtained reaction product was washed and dried to obtain base material core resin particles.

30 parts by weight of the obtained base core resin particles, 23 parts by weight of 2, 2-bis (4-glycidoxyphenyl) propane as a shell molding material, 13.5 parts by weight of 2, 2-bis [4- (4-aminophenoxy) phenyl ] propane, 6.8 parts by weight of polyvinylpyrrolidone as a dispersion stabilizer, and 250 parts by weight of ethanol were put into a reaction vessel and uniformly mixed. Subsequently, the reaction was carried out at 65 ℃ for 24 hours to obtain a reaction product. The obtained reaction product was washed and dried to obtain core-shell particles. Conductive particles, a conductive material, and a connection structure were obtained in the same manner as in example 1, except that the obtained core-shell particles were used as resin particles.

(evaluation)

(1) Differential scanning calorimetry

10mg of the obtained resin particles were heated from 100 ℃ to 350 ℃ at a temperature rise rate of 5 ℃/min under an atmospheric atmosphere, and differential scanning calorimetry was performed. Differential scanning calorimetry was performed using "DSC 6220" manufactured by hitachi high and new technologies. From the obtained measurement results, it was confirmed whether or not an exothermic peak and whether or not an endothermic peak were observed. The exothermic peak is a peak whose exothermic amount is 1000mJ/mg or more, and the endothermic peak is a peak whose endothermic amount is 2000mJ/mg or more.

When the exothermic peak was observed, the peak temperature and the exothermic amount of the exothermic peak having the largest peak area among the observed exothermic peaks were calculated.

(2) Modulus of elasticity in compression of resin particles

The obtained resin particles were measured for the compression elastic modulus (10% K value (A)) when the resin particles were compressed by 10% and the compression elastic modulus (10% K value (B)) when the resin particles were compressed by 10% after heating at 200 ℃ for 10 minutes, by the above-mentioned method, using a micro compression tester ("Fisherscope H-100" manufactured by Fisher Co., Ltd.). From the measurement results, the absolute value of the difference between the 10% K value (A) and the 10% K value (B) was calculated.

(3) Compression recovery rate of resin particles

The resin particles thus obtained were subjected to compression recovery by the method described above using a micro compression tester ("Fisherscope H-100" manufactured by Fisher corporation) to measure the compression recovery rate of the resin particles.

(4) Particle diameter of resin particle and CV value of particle diameter of resin particle

The particle diameters of approximately 100000 resin particles were measured with a particle size distribution measuring instrument ("Multisizer 4" manufactured by Beckman coulter corporation) to calculate the average value of the particle diameters. From the measurement results of the particle diameters of the resin particles, CV values of the particle diameters of the resin particles were calculated according to the following equation.

CV value (%) - (ρ/Dn) × 100

ρ standard deviation of particle diameter of resin particle

Dn is the average value of particle diameters of resin particles

(5) Thickness of conductive part

The obtained conductive particles were added to and dispersed in "Technobit 4000" manufactured by Kulzer, so that the content of the obtained conductive particles was 30% by weight, to prepare an embedding resin for inspection. The cross section of the conductive particles was cut out using an ion milling apparatus ("IM 4000" manufactured by hitachi high and new technologies), and the cross section was passed through the vicinity of the center of the conductive particles dispersed in the embedding resin for inspection.

Subsequently, 20 conductive particles were randomly selected with a magnification of 5 ten thousand using a field emission electron microscope (FE-TEM) (JEM-ARM 200F, manufactured by japan electronics corporation), and the conductive portion of each conductive particle was observed. The thickness of the conductive portion of each conductive particle was measured, and the arithmetic average was taken as the thickness of the conductive portion.

(6) Modulus of elasticity in compression of conductive particles

The resulting conductive particles were measured for the compressive elastic modulus (10% K value (C)) when the conductive particles were compressed by 10% and the compressive elastic modulus (10% K value (D)) when the conductive particles were compressed by 10% after heating at 200 ℃ for 10 minutes, by the above-described method using a micro compression tester ("Fisherscope H-100" manufactured by Fisher corporation). From the measurement results, the absolute value of the difference between the 10% K value (C) and the 10% K value (D) was calculated.

(7) Compression recovery rate of resin particles

The conductive particle compression recovery rate of the obtained conductive particle particles was measured by the above-mentioned method using a micro compression tester ("Fisherscope H-100" manufactured by Fisher corporation).

(8) Adhesion between resin particles and conductive part

The conductive particles in the connecting portion were observed with a scanning electron microscope (Regulus 8220, new hitachi technologies) on the obtained connecting structure. It was confirmed whether or not the conductive portion disposed on the surface of the resin particle was peeled off from the 100 conductive particles observed. The adhesion between the resin particles and the conductive part was determined according to the following criteria.

[ criterion for determining adhesion between resin particles and conductive part ]

O ≈: the number of conductive particles having a conductive portion peeled off was 0

O ^ O: more than 0 and 15 or less conductive particles with conductive parts stripped off

O: more than 15 and 30 or less conductive particles with conductive parts stripped off

And (delta): more than 30 and 50 or less conductive particles with conductive parts stripped off

X: more than 50 conductive particles with conductive parts stripped

(9) Shape-maintaining characteristics of conductive particles

The conductive particles in the connecting portion were observed with a scanning electron microscope (Regulus 8220, new hitachi technologies) on the obtained connecting structure. It was confirmed whether or not the compressed shape was maintained for 100 conductive particles observed. The shape-retaining property of the conductive particles was determined according to the following criteria.

[ criterion for determining shape-retaining characteristics of conductive particles ]

O ≈: the number of the conductive particles maintaining the compressed shape is 90 or more

O ^ O: the number of the conductive particles maintaining the compressed shape is more than 70 and less than 90

O: the number of the conductive particles maintaining the compressed shape is more than 50 and less than 70

And (delta): the number of conductive particles for maintaining the compressed shape is more than 1 and less than 50

X: the conductive particles do not retain a compressed shape or the conductive particles are broken

(10) Connection reliability (between upper and lower electrodes)

The connection resistance between the upper and lower electrodes of each of the 20 obtained connection structures was measured by the 4-terminal method. The average value of the connection resistance was calculated. Further, the connection resistance can be determined by measuring the voltage when a constant current flows, based on the relationship between voltage and current × resistance. The connection reliability was determined according to the following criteria.

[ criterion for determining connection reliability ]

O ≈: the average value of the connection resistance is 1.5 omega or less

O ^ O: the average value of the connection resistance is more than 1.5 omega and less than 2.0 omega

O: the average value of the connection resistance is more than 2.0 omega and less than 5.0 omega

And (delta): the average value of the connection resistance is more than 5.0 omega and less than 10 omega

X: the average value of the connection resistance is more than 10 omega

(11) Impact resistance

The connection structure obtained from the average of the connection reliability of (10) above was dropped from a position having a height of 70cm, and the impact resistance was evaluated by confirming the connection resistance in the same manner as in the evaluation of (10) above. The impact resistance was determined according to the following criteria based on the rate of increase in the resistance value calculated from the average value of the connection resistance obtained in the above evaluation (10).

[ determination criteria for impact resistance ]

O: the rate of increase of resistance value calculated from the average value of the connection resistance is 30% or less

And (delta): the rate of increase of the resistance value calculated from the average value of the connection resistance is more than 30% and not more than 50%

X: the increase rate of the resistance value calculated from the average value of the connection resistance is more than 50%

(12) Connection reliability under high temperature and high humidity conditions

100 connection structures obtained in the above (10) evaluation of connection reliability were left at 85 ℃ and 85% RH for 100 hours. The connection structure after leaving for 100 hours was evaluated for the presence or absence of poor conduction between the upper and lower electrodes. The connection reliability under high temperature and high humidity conditions was judged according to the following criteria.

[ criterion for determining connection reliability under high temperature and high humidity conditions ]

O ^ O: the number of defective conduction occurring in 100 connection structures is 1 or less

O: the number of defective conduction occurring in 100 connection structures is 1 to 5

And (delta): the number of defective conduction occurring in 100 connection structure bodies is 6 or more and 10 or less

X: the number of poor conduction in 100 connecting structures is more than 11

The composition of the material and the results are shown in tables 1 to 5.

[ Table 1]

[ Table 2]

[ Table 3]

[ Table 4]

[ Table 5]

(13) Example of use as spacer for gap control

Preparing a bonding material for ceramic packaging:

in examples 1 to 13, a bonding material for ceramic encapsulation was obtained which contained 30 parts by weight of the obtained resin particles and 70 parts by weight of glass (component: Ag-V-Te-W-P-W-Ba-O, melting point 264 ℃).

Preparing an electronic component device:

the resulting bonding material was used to prepare an electronic component device shown in fig. 5. Specifically, the joining material is applied on the outer peripheral portion of the first ceramic member by a screen printing method. Subsequently, the second ceramic member was placed to face each other, and the joint was irradiated with a semiconductor laser and fired to join the first ceramic member and the second ceramic member.

In the obtained electronic component device, the interval between the first ceramic member and the second ceramic member is well adjusted. In addition, the resulting electronic component device worked well. In addition, the airtightness inside the package is also maintained at a good level.

Description of the figures

1 conductive particle

2 conductive part

11 resin particle

21 conductive particle

22 conductive part

22A first conductive part

22B second conductive part

31 conductive particle

31a projection

32 conductive part

32a projection

33 core material

34 insulating material

41 connection structure

42 first connection object member

42a first electrode

43 second connection object part

43a second electrode

44 connecting part

81 electronic component device

82 first ceramic part

83 second ceramic component

84 joint

84B glass

85 electronic component

86 lead frame

R inner space.