KR20190104625A - Resin composition, the manufacturing method of resin composition, and structure - Google Patents

Abstract

An anisotropic conductive adhesive which can disperse | distribute electroconductive particle by a simple method, and can suppress the short between the electrode terminals of an electronic component, the manufacturing method of an anisotropic conductive adhesive, and a bonded structure are provided. The anisotropic conductive adhesive contains coated conductive particles covered with a part of the surface of the conductive particles by an insulating filler, an insulating filler and an insulating binder, and the coated conductive particles are dispersed in the insulating binder, and the particle diameter of the conductive particles is 7 It is micrometer or more, the particle diameter of the said insulating filler is 0.02 to 0.143% of the particle diameter of the said electroconductive particle, and the quantity of the said insulating filler with respect to the said electroconductive particle is 0.78 to 77 volume%.

Description

Resin composition, the manufacturing method of resin composition, and structure

This technology relates to a resin composition, the manufacturing method of a resin composition, and a structure. This application claims priority based on Japanese Patent Application No. 2017-042220 for which it applied on March 6, 2017 in Japan, and this application is integrated in this application by reference.

In the resin composition containing particle | grains, high dispersibility is calculated | required by particle | grains by various factors, such as the performance fall by aggregation (for example, refer patent document 1). This is especially strongly demanded in resin compositions for electronic parts, adhesives for electronic parts, and the like. This is because it is difficult to maintain the quality stability of the resin composition when the dispersibility of the particles is low.

As an example of the adhesive agent for electronic components, there exists a circuit connection material, The thing in which the electroconductive particle disperse | distributed in the insulating binder is generally used (for example, refer patent documents 2-4). By the way, the electrically-conductive particle in an anisotropic conductive adhesive may aggregate although it is disperse | distributed immediately after manufacture. Aggregation of electroconductive particle becomes a factor, such as a fall of the electroconductive particle trapping efficiency and the short generation between the electrode terminals of an electronic component. Therefore, an insulating film may be previously formed in the surface of electroconductive particle (for example, refer patent document 2).

However, when an insulating film is formed on the surface of electroconductive particle, there exists a tendency for manufacturing cost to increase. In particular, the larger the particle diameter of the conductive particles, the larger the surface area of the conductive particles, the higher the technical difficulty for forming an insulating film on the surface of the conductive particles, and the more the production cost tends to increase. Therefore, even when the particle diameter of electroconductive particle is large, it is calculated | required to disperse | distribute electroconductive particle uniformly by a simple method and to suppress the short between the electrode terminals of an electronic component.

Moreover, even when the particle diameter of the particle | grains disperse | distributed in an insulating binder is small, it is calculated | required to disperse | distribute uniformly.

Japanese Unexamined Patent Publication No. 2015-134887 Japanese Unexamined Patent Publication No. 2015-133301 Japanese Unexamined Patent Publication No. 2014-241281 Japanese Patent Application Laid-Open No. 11-148063

Moreover, this technology is proposed in view of such a conventional situation, and provides the resin composition, the manufacturing method of a resin composition, and a structure which can disperse | distribute a particle uniformly by a simple method.

In the case of an anisotropic conductive adhesive, even when the particle diameter of the conductive particles is large, the anisotropic conductive adhesive can uniformly disperse the conductive particles by a simple method and can suppress the short between the electrode terminals of the electronic component. The manufacturing method of an anisotropic conductive adhesive, and a bonded structure are provided.

The resin composition which concerns on this technique contains the coated large diameter particle | grains by which one part of the surface of large diameter particle was coat | covered with the small particle diameter filler, the small particle diameter filler, and an insulating binder, and the said coated large diameter particle | grains is made to disperse | distribute The particle size of the large-diameter particles is 2 µm or more, the particle size of the small-diameter filler is 0.02 to 5.0% of the particle diameter of the large-diameter particles, and the amount of the small-diameter filler to the large-diameter particles is less than 156 volume%.

The manufacturing method of the resin composition which concerns on this technique is the said large diameter particle by the said small particle diameter filler by stirring the large diameter particle whose average particle diameter is 2 micrometers or more, and the small particle diameter filler whose particle diameter is 0.02-5.0% of the particle diameter of the said large diameter particle. Step (A) of obtaining the first coated particle coated with a thin layer and the second coated particle having a part of the surface of the large diameter particle covered by the small particle diameter filler are stirred by stirring the first coated particle and the insulating binder. It has a process (B) which obtains the resin composition disperse | distributed in an insulating binder, In the said process (A), the said large diameter particle | grains and the said small particle diameter filler are made so that the quantity of the said small particle diameter filler with respect to the said large diameter particle | grains may be less than 156 volume%. Blend. In addition, in this invention, the expression is distinguished and used for particle | grains and a filler in order to make it easy to understand that a size differs.

The anisotropic conductive adhesive according to the present technology includes coated conductive particles covered with a part of the surface of the conductive particles by an insulating filler, an insulating filler, and an insulating binder, wherein the coated conductive particles are dispersed in the insulating binder, The particle diameter of the said electroconductive particle is 7 micrometers or more, the particle diameter of the said insulating filler is 0.02 to 0.143% of the particle diameter of the said electroconductive particle, and the quantity of the said insulating filler with respect to the said electroconductive particle is 0.78-77 volume%.

In the method for producing an anisotropic conductive adhesive according to the present technology, the conductive particles are formed by the insulating filler by stirring conductive particles having an average particle diameter of 7 µm or more and an insulating filler having a particle diameter of 0.02 to 0.143% of the particle diameter of the conductive particles. By agitation of the step (A) of obtaining the coated first coated conductive particles and the first coated conductive particles and the insulating binder, the second coated conductive particles coated with a portion of the surface of the conductive particles by the insulating filler, It has a process (B) of obtaining the anisotropic conductive adhesive dispersed in the said insulating binder, In the said process (A), the said electroconductive particle and the said insulating filler so that the quantity of the said insulating filler with respect to the said electroconductive particle may be 0.78-77 volume%. Compound.

In the bonded structure according to the present technology, the first electronic component and the second electronic component are connected via an anisotropic conductive film made of the anisotropic conductive adhesive.

According to the present technology, by forming a portion of the surface of the large-diameter particles covered with the small-diameter filler, the large-diameter particles can be uniformly dispersed.

According to the present technology, even when the particle diameter of the conductive particles is large, the conductive particles (coated conductive particles covered with a part of the surface of the conductive particles by the insulating filler) can be uniformly dispersed by the simple method, and the electrode of the electronic component Short between terminals can be suppressed.

1 is a cross-sectional view showing an example of a bonded structure according to the present embodiment.
It is a figure which shows an example of the mixture obtained by stirring electroconductive particle and an insulating filler.
It is a figure which shows an example of the anisotropic conductive adhesive obtained by stirring the coating electroconductive particle coated with the insulating filler, and an insulating binder.
It is a figure which shows the electroconductive particle not coat | covered with an insulating filler.
It is a figure which shows an example of the anisotropic conductive adhesive obtained by stirring electrically conductive particle which is not coat | covered with an insulating filler, and an insulating binder.
It is a figure which shows an example of the mixture obtained by stirring electroconductive particle and an insulating filler.
7 is a cross-sectional view schematically showing a first example of some coated particles to which the present technology is applied.
8 is a cross-sectional view schematically showing a second example of some coated particles to which the present technology is applied.
9 is a cross-sectional view schematically showing a third example of some coated particles to which the present technology is applied.

This technique improves the dispersibility of the large diameter particle in an insulating binder by forming some coating particle | grains in which one part of the surface of large diameter particle was coat | covered with the small particle diameter filler. On the other hand, when the whole surface of large diameter particle | grains is coat | covered with the small particle diameter filler, the quantity of the small particle diameter filler with respect to large diameter particle | grains becomes large too much, and there exists a tendency for the dispersibility of the large diameter particle in an insulating binder to fall.

Some coated particles mix (preferably only mix them) the powder of the large-diameter particles and the small-diameter filler, coat the small-diameter filler on the surface of the large-diameter particles, and then mix the mixture with the resin composition ( By kneading), thereby removing some of the small particle size fillers covering the surface of the large diameter particles. Paradoxically speaking, if some coated particles are formed, the amount of the small particle diameter filler to the large diameter particles is an appropriate amount, and it can be said that the dispersibility of the large diameter particles in the insulating binder is high. This can be carried out by applying a high shear (shear force) using, for example, an planetary stirring device or the like, to efficiently coat and partially peel the small particle diameter filler to the surface of the large diameter particles.

Hereinafter, 1st Embodiment is described.

[First embodiment]

<Resin composition>

The resin composition which concerns on this embodiment contains some coating particle | grains by which a part of the surface of the large diameter particle was coat | covered with the small particle diameter filler, the small particle diameter filler, and an insulating binder, and some coating particle is disperse | distributed and a large diameter particle The particle diameter of is 2 micrometers or more, the particle diameter of a small particle diameter filler is 0.02 to 5.0% of the particle diameter of a large diameter particle, and the quantity of the small particle diameter filler with respect to a large diameter particle is less than 156 volume%. In addition, such description as 0.02-5.0% points out 0.02% or more and 5.0% or less unless there is particular notice.

In this specification, the particle diameter of large diameter particle | grains can be made into the value measured by the image type particle size distribution meter (for example, FPIA-3000: Malvern company make). This number is 1000 or more, Preferably it is 2000 or more. Moreover, the particle diameter of a small particle diameter filler can be made into arbitrary 100 average values, for example by electron microscope observation, and can also raise a precision more by setting it as 200 or more.

In addition, the quantity (volume%) of the small particle diameter filler with respect to a large diameter particle | grain can be made into the value calculated | required by following Formula.

Amount (volume%) of small particle diameter filler (B) with respect to large diameter particle (A)

= {(Bw / Bd) / (Aw / Ad)} × 100

Aw: Mass composition (mass%) of large diameter particle (A)

Bw: Mass composition (mass%) of small particle diameter filler (B)

Ad: specific gravity of large diameter particles (A)

Bd: specific gravity of small particle filler (B)

7-9 is sectional drawing which shows typically the 1st-3rd example of the some coating particle to which this technique was applied, respectively. As shown in FIGS. 7-9, some coated particle 20 is coat | covered a part of surface of the large diameter particle 21 by the small particle diameter filler. In other words, some coated particle 20 has the coating part 22 coat | covered with the small particle diameter filler on the surface, and the exposed part 23 which the surface of the large diameter particle was exposed. For example, as for the some covered particle 20, as shown in FIG. 7, the exposed part 23 may be located in the whole surface, and as shown in FIG. 8, the exposed part 23 may exist in a part, and FIG. As shown in the figure, the exposed portion 23 may be half or more of the whole. This is because the first object is to easily obtain the dispersibility of some of the coated large diameter particles obtained by the present method, and it is not because priority is given to the performance of the large diameter particles depending on the coating state.

Some coating particle | grains 20 should just be able to confirm some coating | cover in surface view observation by an electron microscope etc. after making a resin composition into a film form. This preferably changes the observation point a plurality of times to obtain the same result. When confirming in detail, what is necessary is just to be able to confirm that at least one part of outermost surface is coat | covered in the cross section of some covered particles 20. Moreover, by observing the same point in the front and back of the film body to observe, it can confirm more precisely and simply. According to this method, it can discriminate | determine only by determination of the presence or absence of partial coating of large diameter particle | grains. The determination in the case where the peeled small particle diameter filler and the large diameter particle overlap is considered to be possible to determine individually from adjustment of a focal length.

The ratio of the coating | coated part 22 in some coating particle | grains 20 can also be confirmed by surface view observation by an electron microscope etc., for example, after making the above-mentioned resin composition into a film form. Or the resin composition can be hardened or frozen, and the outermost surface of arbitrary 100 partial coverage particle cross sections can be observed under an electron microscope, and can be made into the average value of the ratio of the coating part of arbitrary 100 partial coverage particles. The average value of the ratio of the coating | coated part of such some coating particle | grains may be 15% or more and less than 100%, for example, and may be 30 to 95%.

Moreover, the number ratio of the some covered particle 20 is 70% or more, Preferably it is 80% or more, More preferably, it is 95% or more with respect to the whole of all the covered particle | grains and some covered particle | grains. The number ratio of some of the coated particles 20 is, for example, by curing or freezing the resin composition, electron microscope observation of any 100 of all the coated particles and some of the coated particles, and any 100 of all the coated particles and some of the coating. It may be set as the number of some coated particles to the particles.

A large diameter particle | grain is not specifically limited, A material is suitably selected according to the function of a resin composition. For example, when giving electroconductivity to a resin composition, for example, electroconductive particle, metal particle, etc. are selected, and when giving a spacer function to a resin composition, For example, acrylic rubber, styrene rubber, styrene Olefin rubber, silicone rubber and the like are selected. If coating and partial coating occur in combination with a small particle diameter filler, there is no limitation in particular, It may be an organic substance, an inorganic substance, and may combine the organic substance and inorganic substance like metal plating resin particle. You may use individually by 1 type and may use 2 or more types together. Evaluation of dispersibility becomes easy if it is single 1 type. When it is 2 or more types, it is preferable for the same reason that an external appearance differs clearly.

The particle diameter of large diameter particle | grains is 2 micrometers or more. Moreover, the upper limit of the particle diameter of large diameter particle | grains is not specifically limited, For example, when large diameter particle | grains are electroconductive particle, it is preferable that it is 50 micrometers or less from a viewpoint of the trapping efficiency of the electroconductive particle in a bonded structure, for example, It is more preferable that it is 20 micrometers or less.

Although the number density of the large diameter particle | grains in a resin composition can be suitably adjusted according to the objective, it is preferable that it is 20 pieces / mm <2> or more as a minimum, It is more preferable that it is 100 pieces / mm <2> or more, It is still more preferable that it is 150 pieces / mm <2> or more. . When too small, the adjustment margin in the ratio with a small particle diameter filler decreases, and reproducibility becomes difficult. Moreover, it is preferable that an upper limit is 80000 piece / mm <2> or less, It is more preferable that it is 70000 piece / mm <2> or less, It is still more preferable that it is 65000 piece / mm <2> or less. When the number density of large diameter particle | grains becomes large too much, coating | coating of a small particle diameter filler and mixing with a resin composition will become difficult. The number density is formed in the film form on the smooth surface of a support body, and can be calculated | required from observation in a surface view. The thickness at this time may be 1.3 times or more or 10 micrometers or more of large diameter particles, and an upper limit may be 4 times or less, preferably 2 times or less or 40 micrometers or less of large diameter particles. Since this thickness originates from a resin composition, since it is difficult to determine uniquely, it sets the range in this way. Surface-view observation can use electron microscopes, such as a metal microscope and SEM. Each large diameter particle may be measured and obtained from an observation image, and you may measure using well-known image analysis software (for example, WinROOF (Mitani Corporation) is mentioned). In the case of a resin composition, since it changes with the thickness at the time of making it into a film form, it can be set as the surface field number density by 1.3 times or 4 times the thickness of large diameter particle | grains. In addition, when it contains a solvent, it is set as the thickness after drying.

Most of small particle size fillers are disperse | distributed in an insulating binder, and a part coat | covers a part of surface of large diameter particle | grains. An insulating filler can be used as a small particle diameter filler. Examples of the insulating filler include oxides such as titanium oxide, aluminum oxide, silica, calcium oxide and magnesium oxide, hydroxides such as calcium hydroxide, magnesium hydroxide and aluminum hydroxide, calcium carbonate, magnesium carbonate, zinc carbonate and barium carbonate. Sulfates, such as a carbonate, calcium sulfate, and barium sulfate, Silicates, such as a calcium silicate, Nitrides, such as aluminum nitride, boron nitride, and silicon nitride, etc. are mentioned. An insulating filler may be used individually by 1 type, and may use 2 or more types together.

The upper limit of the particle size of the small particle size filler may be 14% or less, preferably 0.3% or less of the large diameter particles. Or it is preferable that it is 100 nm or less, and it is more preferable that it is 50 nm or less. When the small particle diameter filler is not too large with respect to the surface area of the large diameter particles, problems such as scratches on the surface of the large diameter particles can be suppressed. Moreover, it is preferable that the minimum of the particle diameter of a small particle diameter filler is 10 nm or more. By small particle diameter filler not being too small with respect to the surface area of large diameter particle | grains, aggregation of large diameter particle | grains can be suppressed more effectively. When too small, the viscosity of a resin composition raises too much and the influence on dispersibility is also concerned.

From the relationship between the size of the large-diameter particles and the small-particle filler described above, the ratio of the particle diameter of the large-diameter particles and the small-particle filler (the particle diameter of the small-diameter filler / particle diameter of the large-diameter particles) is 0.02 to 5.0%, and is 0.02 to 2.5%. It is preferable.

Moreover, the volume ratio of the small particle diameter filler with respect to the large diameter particle which satisfy | fills the ratio of the particle diameter mentioned above is less than 156 volume%. If it exceeds this, uniform dispersion in resin will become difficult to be obtained easily. In addition, although a lower limit may exceed 0%, it is difficult to determine uniquely since these shapes etc. are related besides the ratio of the size of a large diameter particle | grain and a small particle diameter filler. However, it is considered that there is no problem in particular if it is 0.78% or more, It is preferable in it being 3.9% or more, More preferably, it is 7.8% or more. Moreover, it is preferable that it is 78 volume% or less, and, as for an upper limit, it is more preferable that it is 39% or less. In addition, these numerical values can be suitably selected from the relationship of a large diameter particle | grain and a small particle diameter filler. By satisfy | filling such conditions, the dispersibility of large diameter particle | grains can be made favorable.

As the insulating binder (insulating resin), a known insulating binder can be used. As a hardening type, a thermosetting type, a photocuring type, the hardening type for photothermal combined use, etc. are mentioned. For example, radical photopolymerization resin containing a (meth) acrylate compound and a radical photopolymerization initiator, thermal radical polymerization type resin containing a (meth) acrylate compound and a thermal radical polymerization initiator, an epoxy compound, and a thermal cationic Thermal cation polymerization type resin containing a polymerization initiator, thermal anion polymerization type resin containing an epoxy compound and a thermal anion polymerization initiator, etc. are mentioned. Moreover, you may use a well-known adhesive composition.

The resin composition may further contain other components other than some coating particle | grains, a small particle diameter filler, and an insulating binder as needed. As another component, a solvent (methyl ethyl ketone, toluene, propylene glycol monomethyl ether acetate etc.), a stress relaxation agent, a silane coupling agent etc. are mentioned, for example.

As described above, the resin composition has a particle diameter of the large diameter particles of 2 µm or more, a particle diameter of the small particle diameter filler is 0.02 to 5.0% of the particle size of the large diameter particle, and the amount of the small particle diameter filler to the large diameter particle is less than 156 volume%. As a result, it has high dispersibility.

For example, when a resin composition functions as a spacer between a 1st member and a 2nd member, since the quantity of the small particle diameter filler adhering to a large diameter particle is small, it can be set as the spacer of the substantially diameter of a large diameter particle. For example, when the resin composition is an anisotropic conductive adhesive whose large diameter particles are conductive particles and the small particle diameter filler is an insulating filler, since the amount of the insulating filler adhered to the conductive particles is small, excellent conductivity can be obtained. .

For example, when the resin composition is an anisotropic conductive film made of an anisotropic conductive adhesive whose large diameter particles are conductive particles and the small particle diameter filler is an insulating filler, since the dispersibility of the conductive particles is very high, the entire anisotropic conductive film The difference between the number density (pieces / mm 2) of the conductive particles and the number density (pieces / mm 2) of the conductive particles in a 0.2 mm × 0.2 mm region arbitrarily extracted from the anisotropic conductive film can be 15% or less. Here, the difference in the number density is the difference between the maximum value and the minimum value of the number density of the conductive particles in a predetermined region which is arbitrarily extracted.

<Method for producing resin composition>

The manufacturing method of the resin composition which concerns on this embodiment has the following process (A) and a process (B).

[Step (A)]

In a process (A), a 1st coating particle is obtained by stirring a large diameter particle | grain and a small particle diameter filler whose particle diameter is smaller than a large diameter particle. In process (A), in order to suppress aggregation of the 2nd coating particle obtained by process (B), a large diameter particle is coat | covered with a small particle diameter filler. Moreover, in a process (A), large diameter particle | grains and a small particle diameter filler are mix | blended so that the quantity of the small particle diameter filler with respect to large diameter particle | grains may be less than 156 volume%. By satisfying such conditions, the coating of the small particle diameter filler on the surface of the large diameter particle is easily carried out in the step (A), and the small particle diameter filler in the first coated particle is easily separated in the step (B). You can.

The method of stirring a large diameter particle | grain and a small particle diameter filler may be any of a dry method and a wet method, and a dry method is preferable. This is because the technique used in known toners and the like can be applied. As an apparatus for stirring a large diameter particle | grain and a small particle diameter filler, an planetary stirring apparatus, a shaker, a laboratory mixer, a stirring propeller, etc. are mentioned, for example. In particular, from the viewpoint of coating large diameter particles having a relatively large average particle diameter with the insulating filler, a planetary stirring device to which a high shear is applied is preferable. The method of using a medium such as a ball mill or a bead mill is not preferred, although it is not excluded. It is because it is not preferable on productivity if it removes other than a large diameter particle | grain and a small particle diameter filler. Moreover, when using such a medium (ball or beads), since the factor which considers the influence on the surface state of a large diameter particle | grain and a small particle diameter filler increases, product design becomes difficult. The planetary stirring device refers to a stirring device of a system in which a container containing a material (a mixture of large diameter particles and small particle diameter filler) is rotated while rotating. In the case of the batch system produced every time in a container, it is also preferable at the point which becomes easy to control quality. That is, the resin composition in which the large diameter particle | grains and the small particle diameter filler were disperse | distributed easily with high precision is easy to be obtained.

The large diameter particle | grains and the small particle diameter filler have the same preferable range as the large diameter particle | grains and small particle diameter filler demonstrated by the above-mentioned anisotropic conductive adhesive agent. In particular, in the step (A), from the viewpoint of coating the large diameter particles with the small particle diameter filler, it is preferable to use the large diameter particles in a dry powder state.

[Step (B)]

In the step (B), by stirring the first coated particles and the insulating binder, a resin composition obtained by dispersing the second coated particles and the small particle size filler separated from the large diameter particles in the first coated particles in the insulating binder is obtained. .

In the step (B), the small particle diameter filler is separated from the large diameter particle by adding friction with the large diameter particle or high shear to the small particle diameter filler in the first coated particle by stirring the first coated particle in the insulating binder. Thus, some coated particles (second coated particles) in which part of the surface of the large diameter particles is coated on the small particle diameter filler are obtained. Moreover, since the small particle diameter filler separated from the large diameter particle in a 1st covering particle is interposed between 2nd covering particle, aggregation of a 2nd covering particle can be suppressed. Thus, by performing a process (B), aggregation of a 2nd coating particle can be suppressed and a 2nd coating particle can be disperse | distributed in an insulating binder. At this time, the small particle diameter filler is also dispersed at the same time. That is, in this invention, the mixing process may be a minimum number of times. For example, although a small particle diameter filler may be added every time for viscosity adjustment like conventionally, it can be anticipated easily that it is difficult to acquire the reproducibility of a dispersed state. However, since a required amount can be prepared by preparing powder (large diameter particle | grain and a small particle diameter filler) beforehand, and mix | blending a resin composition with it, it is also preferable from a viewpoint of a material cost and a manufacturing cost. Moreover, since it is easy to compare also about the batch which has the problem of dispersibility, the analysis of a defect factor becomes easy, and there exists a merit also in terms of quality control as mentioned above. Moreover, in the case of batch type, there are merit that there are few factors to consider, such as when transitioning from a small amount of development examination to a mass production. Moreover, for the same reason, it is preferable also on productivity and quality control to perform process (A) and process (B) using the same container and the same planetary stirring apparatus. It can be expected to suppress the influence of contamination. In the case of mass production, it is only necessary to increase the same apparatus. In short, it is possible to cope with a small quantity of various kinds and can also cope with scale up. Therefore, adjustment of production management also becomes easy.

In addition, coating the surface of a large diameter filler with a small particle diameter filler sufficiently small in terms of maintaining the quality of the surface state of the conductive particles when the conductive particles which are large diameter particles are sandwiched by the terminal, such as anisotropic conductive connections as described later. desirable. That is, the small particle diameter filler coat | covers and interposes the regular of the surface state by contacting with large diameter particle | grains, and can expect the function to be protected. In addition, since the coating is released by mixing (kneading), it is hard to think that some coatings hinder conduction when a direct force such as sandwiched between the terminals is applied to the large diameter particles. Moreover, also in insulation between terminal arrangements, although the large diameter particle | grains maintain high dispersibility, and also hold | maintain some coating | covering at the same time, it is thought that the short (produced by connecting large diameter particle | grains) is in the state which is easy to avoid. When the specific effect is illustrated, in the case of the electroconductive particle whose large diameter particle | grain is a metal plating resin particle, it can be expected that the range of selection becomes wider than before regarding the thickness and material of metal plating, the hardness of resin particle, etc. The same thing can be said about using it together with a spacer.

The method of stirring a 1st coating particle and an insulating binder is not specifically limited, The stirring method in the above-mentioned process (A) can be employ | adopted. In particular, from the viewpoint of separating the small particle diameter filler constituting the first coated particle when the first coated particle and the insulating binder are stirred, a stirring method in which a high shear is applied, for example, a stirring method using a planetary stirring device is preferable. Do. By using the planetary stirring device, friction and high shear of the large diameter particles and the small particle filler in the first coated particle are applied in the insulating binder, so that a suitable deviation between the small particle filler and the small particle filler in the first coated particle is obtained. I think it happens.

According to the manufacturing method which has the above process (A) and a process (B), the resin composition which the 2nd coating particle disperse | distributed in an insulating binder is obtained by a simple method. In addition, this manufacturing method may further have other processes other than the process (A) and process (B) mentioned above as needed. In addition, it is preferable from a viewpoint of productivity and quality to perform process (A) and a process (B) by the same container and the same apparatus (oil-type mixing apparatus) as mentioned above.

<Structure>

As for the structure which concerns on this embodiment, the 1st member and the 2nd member are adhere | attached through the resin composition mentioned above. If a resin composition is curable resin, it may be made to harden | cure and fix it, and if it is an adhesive, you may just stick. As an example, for example, a mold may be filled with a resin composition and cured to obtain a molded article. For example, when a resin composition functions as a spacer between a 1st member and a 2nd member, since the quantity of the small particle diameter filler adhering to a large diameter particle is small, it can be set as the spacer of the substantially diameter of a large diameter particle. For example, when the resin composition is a conductive adhesive whose large diameter particles are conductive particles and the small particle diameter filler is an insulating filler, the amount of the insulating filler adhered to the conductive particles is small, so that excellent conductivity can be obtained. In the case of an anisotropic conductive adhesive, since the relationship between the terminal and the terminal arrangement is more complicated, this effect can be more exhibited. In addition, these may be made into a film body beforehand.

Moreover, this invention also includes the structure which connects a 1st article and a 2nd article using a resin composition as an adhesive agent or an adhesive film, and its manufacturing method. These articles may be electronic components, and may be provided with a conducting portion (anisotropy is not essential), but may be conductive, but is not limited thereto. Moreover, this invention also includes the thing which bonded together the 1st article and the 2nd article, and the bonding method with or without adhesiveness. In short, it becomes a bonding body of a 1st article and a 2nd article, and a bonding method which pressurizes these. Moreover, what formed the resin composition and its film body only in a 1st article is also included in this invention. This may be bonded to the first article as a coating or film. If a resin composition is an adhesive, it will form an adhesion layer. It can also be set as an adhesive film by forming in a support body.

Hereinafter, 2nd Embodiment is described.

Second Embodiment

<Anisotropic Conductive Adhesive>

The anisotropic conductive adhesive agent which concerns on this embodiment contains the coating conductive particle (second coating conductive particle mentioned later) in which one part of the surface of the conductive particle was coat | covered with the insulating filler, an insulating filler, and an insulating binder, and this coating conductive Particles are dispersed in an insulating binder. In addition, in the following description, the electrically-conductive particle whose average particle diameter is 7 micrometers or more and the electrically conductive particle coat | covered by the insulating filler obtained by stirring the insulating filler are called "1st covering conductive particle." In addition, the coating conductive particle in which one part of the surface of the conductive particle was coat | covered by the insulating filler obtained by stirring a 1st coating conductive particle and an insulating binder is called "second coating conductive particle."

The anisotropic conductive adhesive may be either an anisotropic conductive film (ACF) or a anisotropic conductive paste (ACP). An anisotropic conductive film is preferable at the point of ease of handling, and an anisotropic conductive paste is preferable at the point of cost.

Hereinafter, the 2nd coating electroconductive particle (conductive particle, insulating filler) which comprises an anisotropic conductive adhesive agent, an insulating binder, and the other component which may contain further are demonstrated.

[Conductive Particles]

The material of the conductive particles is not particularly limited. For example, metal particle | grains, such as nickel, copper, gold, silver, and palladium, metal coating resin particle | grains which coat | covered the surface of the resin particle with metal, etc. are mentioned. As the resin particles in the metal-coated resin particles, for example, particles of an epoxy resin, a phenol resin, an acrylic resin, an acrylonitrile styrene resin, a benzoguanamine resin, a divinylbenzene resin, or a styrene resin can be used. Can be. Electroconductive particle may be used individually by 1 type, and may use 2 or more types together.

The particle diameter of the conductive particles is 7 µm or more. The upper limit of the particle diameter of the conductive particles is not particularly limited, but is preferably 50 µm or less from the viewpoint of the trapping efficiency of the conductive particles in the bonded structure. The particle size of the conductive particles can be measured by an image type particle size distribution meter (as an example, FPIA-3000: manufactured by Malvern). It is preferable to obtain by measuring 1000 or more, preferably 2000 or more.

[Insulating filler]

As the insulating filler, insulating inorganic particles can be used. For example, oxides such as titanium oxide, aluminum oxide, silica, calcium oxide, magnesium oxide, hydroxides such as calcium hydroxide, magnesium hydroxide, aluminum hydroxide, carbonates such as calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, calcium sulfate, Sulfates, such as barium sulfate, Silicates, such as a calcium silicate, Nitrides, such as aluminum nitride, boron nitride, and silicon nitride, etc. are mentioned. An insulating filler may be used individually by 1 type, and may use 2 or more types together.

With respect to the relationship between the size of the conductive particles and the insulating filler (particle diameter), the insulating filler is significantly smaller with respect to the surface area of the conductive particles, so that the coating and the separation of the insulating filler on the surface of the conductive particles easily proceed. Thus, when the first coated conductive particles are stirred in the insulating binder, the insulating filler separated from the conductive particles in the first coated conductive particles is interposed between the second coated conductive particles, thereby suppressing aggregation of the second coated conductive particles. Can be. Accordingly, the second coated conductive particles can be uniformly dispersed in the insulating binder.

Specifically, the upper limit of the particle diameter of the insulating filler is preferably 1000 nm or less, and more preferably 50 nm or less. When the insulating filler is not too large with respect to the surface area of the conductive particles, problems such as scratches on the surface of the conductive particles can be suppressed. Moreover, it is preferable that the minimum of the particle diameter of an insulating filler is 10 nm or more. When the insulating filler is not too small with respect to the surface area of the conductive particles, aggregation of the conductive particles can be more effectively suppressed. The particle diameter of an insulating filler can be calculated | required from observation results, such as an electron microscope.

From the relationship of the magnitude | size of the electrically conductive particle and insulating filler demonstrated above, the ratio of the particle diameter of the electrically conductive particle and the insulating filler (particle diameter of the insulating filler / particle diameter of the electrically conductive particle) is 0.02 to 0.143%, and it is preferable that it is 0.02 to 0.10%. .

Moreover, the number ratio of the insulating filler with respect to the electrically-conductive particle which satisfy | fills the ratio of the particle diameter mentioned above, ie, the quantity of the insulating filler with respect to one electrically-conductive particle, is 0.78-77 volume%, It is preferable that it is 3.9-38.7 volume%, It is more preferable that it is 7.7-15.5 volume%. By satisfy | filling such conditions, the dispersibility of electroconductive particle can be made favorable.

[Insulating binder]

As the insulating binder (insulating resin), an insulating binder used in a known anisotropic conductive adhesive can be used. As a hardening type, a thermosetting type, a photocuring type, the hardening type for photothermal combined use, etc. are mentioned. For example, radical photopolymerization resin containing a (meth) acrylate compound and a radical photopolymerization initiator, thermal radical polymerization type resin containing a (meth) acrylate compound and a thermal radical polymerization initiator, an epoxy compound, and a thermal cationic Thermal cation polymerization type resin containing a polymerization initiator, thermal anion polymerization type resin containing an epoxy compound and a thermal anion polymerization initiator, etc. are mentioned.

Hereinafter, the thermal anion polymerization type insulating binder containing film forming resin, an epoxy resin, and a latent hardening | curing agent is demonstrated as a specific example.

As for film formation resin, resin whose average molecular weight is about 10000-80000 is preferable. As film formation resin, various resins, such as an epoxy resin, a modified epoxy resin, a urethane resin, and a phenoxy resin, are mentioned. Among these, a phenoxy resin is preferable from a viewpoint of a film formation state, connection reliability, etc. Film formation resin may be used individually by 1 type, and may use 2 or more types together.

Although it does not specifically limit as an epoxy resin, For example, a naphthalene type epoxy resin, a biphenyl type epoxy resin, a phenol novolak-type epoxy resin, a bisphenol type epoxy resin, a stilbene type epoxy resin, a triphenol methane type epoxy resin, a phenol Aralkyl type epoxy resins, naphthol type epoxy resins, dicyclopentadiene type epoxy resins, triphenylmethane type epoxy resins, and the like. An epoxy resin may be used individually by 1 type, and may use 2 or more types together.

As a latent hardening | curing agent, acid generators, such as an imidazole series, a hydrazide system, an amine imide, a dicyandiamide, or an antimony system, phosphorus system, a fluorine system, etc. are mentioned, for example. These can be used individually or in combination of 2 or more types. Among these, the microcapsule type which coat | covered the surface of the imidazole compound particle with hardened | cured material, such as a polyurethane system and polyester type, is used preferably. Moreover, you may use the master batch type hardening | curing agent which disperse | distributes a microcapsule type hardening | curing agent in a liquid epoxy resin.

[Other Ingredients]

The anisotropic conductive adhesive may further contain other components other than 2nd covering electroconductive particle and an insulating binder as needed. As another component, a solvent (methyl ethyl ketone, toluene, propylene glycol monomethyl ether acetate etc.), a stress relaxation agent, a silane coupling agent etc. are mentioned, for example. Moreover, the anisotropic conductive adhesive may further contain the insulating filler isolated from the electroconductive particle in a 1st covering electroconductive particle.

As described above, the anisotropic conductive adhesive has a particle diameter of the conductive particles of 7 µm or more, a particle diameter of the insulating filler is 0.02 to 0.143% of the particle diameter of the conductive particles, and the amount of the insulating filler to the conductive particles is 0.78 to 77 volume%. . When the first coated conductive particles are stirred in the insulating binder, the first coated conductive particles are separated from the conductive particles in the first coated conductive particles. Therefore, the coated insulating filler sometimes obtains the second coated conductive particles remaining on the particle surface, and such a remaining state can be confirmed by a known observation method (electron microscope such as SEM or TEM). It can be confirmed whether it is obtained by the method of this invention by the residual state of such an insulating filler and the dispersion state of electroconductive particle.

The anisotropic conductive adhesive can suppress the aggregation of the second coated conductive particles because the insulating filler separated from the conductive particles in the first coated conductive particles is interposed between the second coated conductive particles. Therefore, the 2nd covering electroconductive particle can be disperse | distributed in an insulating binder, and the short between the electrode terminals of an electronic component can be suppressed. Moreover, in the anisotropic conductive adhesive agent, the insulating filler which isolate | separated from the conductive particle in a 1st coating conductive particle by stirring of a 1st coating conductive particle and an insulating binder in the vicinity of the 2nd coating conductive particle in an insulating binder is fixed ratio. Uniformly present. In such an anisotropic conductive adhesive, high correlation is exhibited in the dispersed state of the 2nd coating conductive particle and the area | region where an insulating filler exists, and the conductive particle capture rate can be stabilized.

In addition, in the present technology, the insulating filler is simply coated on relatively large conductive particles of 7 µm or more, and separated at the time of kneading into the insulating binder, so that the surface (conductive layer) of the conductive particles is not previously subjected to insulation treatment. Sufficient short suppression effect can be obtained. That is, there is no trace of the insulation treatment except for the insulating filler remaining in a small amount without being separated from the conductive layer of the conductive particles. Therefore, it is excellent in the handleability of electroconductive particle and also advantageous in cost. Also in the design of an anisotropic electrically conductive adhesive agent, when there are few parameters, there is an advantage also in development. Moreover, by using the electrically-conductive particle which pre-insulated by the well-known method, the performance improvement by using the electrically conductive particle excellent in insulation, and the freedom of design can also be increased. Therefore, this technique does not exclude the aspect which uses what performed the insulation process previously to the surface (electroconductive layer) of electroconductive particle.

<Method for Producing Anisotropic Conductive Adhesive>

The manufacturing method of the anisotropic conductive adhesive agent which concerns on this embodiment has the following process (A) and process (B).

[Step (A)]

In a process (A), a 1st covering electroconductive particle is obtained by stirring the electrically-conductive particle whose average particle diameter is 7 micrometers or more, and the insulating filler which is 0.02 to 0.143% of the particle diameter of a particle diameter electroconductive particle. In process (A), in order to suppress aggregation of the 2nd coating electroconductive particle obtained by process (B), electroconductive particle is coat | covered with an insulating filler. Moreover, in a process (A), as above-mentioned, electroconductive particle and insulating filler are mix | blended so that the quantity of the insulating filler with respect to electroconductive particle may be 0.78-77 volume%. By satisfying such conditions, the coating of the insulating filler on the surface of the conductive particles can be easily carried out in the step (A), and the insulating filler in the first coated conductive particles can be easily separated in the step (B). Can be.

The method of stirring electroconductive particle and an insulating filler may be any of a dry method and a wet method, and a dry method is preferable. As an apparatus for stirring electroconductive particle and an insulating filler, an planetary stirring apparatus, a shaker, a laboratory mixer, a stirring propeller, etc. are mentioned, for example. In particular, from the viewpoint of coating the conductive particles having a relatively large average particle diameter with the insulating filler, a planetary stirring device to which a high shear is applied is preferable. The planetary stirring device refers to a stirring device of a system in which a container containing a material (a mixture of conductive particles and insulating filler) is revolved while rotating.

The conductive particles and the insulating filler have the same preferred ranges as the conductive particles and the insulating filler described in the above-described anisotropic conductive adhesive. In particular, from the viewpoint of coating the conductive particles with the insulating filler in the step (A), it is preferable to use the conductive particles in a dry powder state.

[Step (B)]

In the step (B), by stirring the first coated conductive particles and the insulating binder, the insulating filler separated from the second coated conductive particles and the conductive particles in the first coated conductive particles is dispersed in the insulating binder. Is obtained.

In the step (B), the insulating filler is separated from the conductive particles by adding friction with the conductive particles or high shear to the insulating filler in the first coated conductive particles by stirring the first coated conductive particles in the insulating binder. Thus, coated conductive particles (second coated conductive particles) in which part of the surface of the conductive particles is coated with the insulating filler are obtained. Moreover, since the insulating filler which isolate | separated from the electroconductive particle in a 1st covering electroconductive particle is interposed between 2nd covering electroconductive particle, aggregation of a 2nd covering electroconductive particle can be suppressed. Thus, by performing a process (B), aggregation of a 2nd coating conductive particle can be suppressed and a 2nd coating conductive particle can be disperse | distributed in an insulating binder.

The method of stirring the 1st covering electroconductive particle and an insulating binder is not specifically limited, The stirring method in the above-mentioned process (A) can be employ | adopted. In particular, when the first coated conductive particles and the insulating binder are stirred, a stirring method in which a high shear is applied, for example, a stirring method using a planetary stirring device, from the viewpoint of separating the insulating filler constituting the first coated conductive particles, desirable. By using the planetary stirring device, the friction between the conductive particles and the insulating filler in the first coated conductive particles and high shear is applied, so that a deviation of the insulating filler may occur from the conductive particles in the first coated conductive particles. .

According to the manufacturing method which has the above process (A) and a process (B), the anisotropic conductive adhesive agent by which the 2nd coating conductive particle was disperse | distributed in the insulating binder by a simple method is obtained. By using this anisotropic conductive adhesive, the short between the electrode terminals of an electronic component can be suppressed. Moreover, when process (A) and process (B) are performed by the same container and the same apparatus (oil-type mixing apparatus), even from the aspect of manufacturing process, the surface of quality control, such as prevention of contamination mixing, Also, it becomes preferable.

In addition, this manufacturing method may further have other processes other than the process (A) and process (B) mentioned above as needed.

<Anisotropic Conductive Film>

The anisotropic conductive film which concerns on this embodiment consists of an anisotropic conductive adhesive mentioned above, and the 2nd coating conductive particle mentioned above is disperse | distributed to the adhesive bond layer which consists of an insulating binder. For example, the number density (piece / mm <2>) of the 2nd covering electroconductive particle of the whole anisotropic conductive film (for example, 1.0 mm x 1.0 mm), and the narrow area | region extracted arbitrarily in the anisotropic conductive film (for example, 0.2 mm) It is preferable that the difference of the number density (piece / mm <2>) of the 2nd covering electroconductive particle in (x 0.2 mm) is 15% or less, It is more preferable that it is 10% or less, It is substantially the same (for example, within 5%) Even more preferred. Moreover, when using for connection as an anisotropic electrically conductive paste, it is preferable that the same dispersibility is obtained as an example. This can be confirmed by making it layered on smooth surfaces, such as a support body.

Thus, since the difference of the number density of the 2nd covering conductive particles of the whole anisotropic conductive film and the number density of the 2nd covering conductive particles in the narrow region extracted arbitrarily of the anisotropic conductive film is small, a 2nd covering conductive particle is made into the whole film. It can be confirmed that it is uniformly dispersed over. Therefore, the electroconductive particle trapping rate is stabilized and the conduction defect and the short can be suppressed. When the 2nd coating conductive particle is disperse | distributed uniformly over the whole film, there exists an effect which can also reduce the man-hour of the quality inspection itself of an anisotropic conductive film. It is because it becomes easy to find when there exists regular aggregation when it is disperse | distributing uniformly. Therefore, the effect is more exhibited especially when the length is set to 10 m or more. Moreover, when anisotropic conductive film is 10 m or more, Preferably it is 50 m or more, since it can connect continuously, there is also the effect of cost reduction of the manufacturing method of a bonded structure. Although there is no long upper limit in particular, 5000 m or less is preferable, 1000 m or less is more preferable, and 600 m or less is more preferable at the point of minimizing improvement of a connection device, and handling.

Moreover, when the electrically-conductive particle diameter is comparatively large like 7 micrometers or more like this invention, it is suitable for the connection of the electronic component to be connected whose surface is not smoother than glass, such as a ceramic substrate (having curvature on the surface). Moreover, since comparatively large electroconductive particle is disperse | distributed uniformly like this, even if it has the curvature in the connected electronic component, it is hard to be influenced by capture | acquisition by the flow of resin at the time of connection. This is because when the conductive particles are agglomerated, the terminal surface on which the conductive particles are trapped due to bending is not constant, so that the trapped state for each terminal cannot be kept constant.

The particle density of the second coated conductive particles in the anisotropic conductive film is not particularly limited as long as both the conduction reliability and the short suppression can be achieved. However, as an example, if it is too small, it becomes difficult to satisfy the conduction reliability. Is preferable and 100 pieces / mm <2> or more is more preferable. Moreover, as an upper limit, since the risk of short generation becomes high, as an example, 3000 piece / mm <2> or less is preferable, 2000 piece / mm <2> or less is more preferable, 1000 piece / mm <2> or less is more preferable. What is necessary is just to adjust these suitably according to the terminal size connected with a conductive particle diameter. Moreover, also when using an anisotropic electrically conductive paste, the same thing is preferable as an example. This can be confirmed by making it layered on smooth surfaces, such as a support body.

The upper limit of the area occupancy in the plan view of the second coated conductive particles in the anisotropic conductive film is preferably 80% or less, more preferably 75% or less, and even more preferably 70% or less. Such a high area occupancy is due to the high uniformity of the second coating conductive particles being kneaded with the insulating resin, although they may differ depending on the ratio of the thickness and the particle diameter of the anisotropic conductive film. It can be said that one of the features of the present invention can avoid the risk of occurrence of a short even in such a high area occupancy. Moreover, when using for connection as an anisotropic electrically conductive paste, it is preferable that the same dispersibility is obtained as an example. This can be confirmed by making it layered on smooth surfaces, such as a support body.

The lower limit of the area occupancy in the plan view of the second coated conductive particles in the anisotropic conductive film may vary depending on the thickness and the particle diameter ratio of the anisotropic conductive film. It can be ensured and it is preferable practically that it is larger than 5%, and it is more preferable that it is larger than 10%. Moreover, also when using an anisotropic electrically conductive paste, the same thing is preferable as an example. This can be confirmed by making it layered on smooth surfaces, such as a support body.

The area occupancy in the plan view of the second coated conductive particles in the anisotropic conductive film can be calculated based on observation by an electron microscope such as an optical microscope, a metal microscope, or an SEM. You may measure using well-known image analysis software (For example, WinROOF (Mitani Corporation) is mentioned). Moreover, the calculated area of area occupancy may be the same as an example of the area which calculates | requires a number density, and may calculate | require from a larger area (for example, 2 mm x 2 mm or 5 mm x 5 mm). Moreover, when using for connection as an anisotropic electrically conductive paste, it is preferable that the same dispersibility is obtained as an example. This can be confirmed by making it layered on smooth surfaces, such as a support body.

As a formation method of an anisotropic conductive film, the method of film-forming and drying an anisotropic conductive adhesive agent by a coating method is mentioned, for example. For example, the lower limit of the thickness of the anisotropic conductive film may be the same as the particle diameter, and preferably 1.3 times or more or 10 μm or more of the particle diameter. For example, an upper limit can be 40 micrometers or less or 2 times or less of a particle diameter. Moreover, an anisotropic conductive film can be formed on a peeling film.

<Connection structure>

In the connection structure which concerns on this embodiment, the 1st electronic component and the 2nd electronic component are connected through the anisotropic conductive film mentioned above. For example, as shown in FIG. 1, the bonded structure 1 is the 1st which consists of several terminal 4a through the electrically-conductive particle (2nd covering electroconductive particle) 3 in the anisotropic conductive film 2 A second electronic component 5 having a first electronic component 5 having a terminal string 4 and a second terminal string 6 facing the first terminal string 4 and comprising a plurality of terminals 6a; 7) is connected.

There is no restriction | limiting in particular in a 1st electronic component and a 2nd electronic component, According to the objective, it can select suitably. As a 1st electronic component, a flexible substrate (FPC: Flexible Printed Circuits), a transparent substrate, etc. are mentioned, for example. The transparent substrate is not particularly limited as long as it has high transparency, and examples thereof include a glass substrate and a plastic substrate. Moreover, as a 2nd electronic component, a camera module, an IC (Integrated Circuit) module, an IC chip, etc. are mentioned, for example. The second electronic component may be a functional module on which a sensor is mounted. In the camera module, a ceramic substrate is sometimes used from the viewpoint of excellent electrical insulation and thermal insulation. Ceramic substrates and functional modules have advantages such as excellent dimensional stability in downsizing (for example, 1 cm 2 or less).

<Method for Manufacturing Connected Structure>

The manufacturing method of the bonded structure which concerns on this embodiment is equipped with the 1st electronic component 5 provided with the 1st terminal string 4, and the 2nd terminal string 6 which opposes the 1st terminal string 4. And compressing the second electronic component 7 to be made through the anisotropic conductive film described above. Thereby, the 1st terminal string 4 and the 2nd terminal string 6 can be connected through the electroconductive particle 3.

The 1st electronic component 5 and the 2nd electronic component 7 are the same as the 1st electronic component 5 and the 2nd electronic component 7 in the connection structure mentioned above. Moreover, also about an anisotropic conductive adhesive agent, it is the same as that of the anisotropic conductive adhesive agent mentioned above.

Example

Hereinafter, a first embodiment of the present technology will be described.

Experimental Example 1

[Production of Anisotropic Conductive Adhesive (Resin Composition)]

1 g of conductive particles (large diameter particles, Ni plating (thickness 115 nm), resin core, specific gravity 3.44 g / cm 3) having an average particle diameter of 3 μm, and a silica filler (small particle diameter filler, product particle size: 10 nm) as an insulating filler 0.5 g (78.2% by volume of conductive particles) was added to YA010C and specific gravity 2.2 g / cm 3) to a planetary stirring device (product name: Awatori Renta, manufactured by THINKY), and stirred for 5 minutes to conduct conductive particles and A mixture of insulating fillers was prepared.

About the ratio of the number of insulating fillers, it evaluated with "suitable quantity", "excess", and "lack". Specifically, the case where the ratio of the number of silica fillers to the conductive particles, that is, the amount of the silica fillers to the conductive particles, was in the range of more than 1.56% by volume and less than 156% by volume was evaluated as "suitable amount." Moreover, when the quantity of the silica filler with respect to electroconductive particle exceeds 156 volume%, it evaluated as "excess." In addition, the case where the quantity of the silica filler with respect to electroconductive particle is less than 1.56 volume% was evaluated as "lack".

A mixture of the conductive particles and the insulating filler and an insulating binder composed of the following components were added to a planetary stirring device (product name: Awatori Renta, manufactured by THINKY), and stirred for 1 minute to prepare an anisotropic conductive adhesive.

The insulating binder is an epoxy resin (EP828: manufactured by Mitsubishi Chemical Corporation); 20 g and phenoxy resin (YP-50: manufactured by Shinnitetsu Sumkin Chemical Co., Ltd.); 30 g and a curing agent (Novacure 3941HP, manufactured by Asahi Chemical Co., Ltd.); 50 g of the mixture was diluted with toluene, adjusted, and mixed.

[Production of Anisotropic Conductive Film (Film Body)]

The anisotropic conductive adhesive was apply | coated on PET film, it dried for 5 minutes in 80 degreeC oven, and the adhesion layer which consists of an anisotropic conductive adhesive was formed on PET film. This obtained the anisotropic conductive film of thickness 12micrometer (4 times the particle diameter of a large diameter particle). Moreover, it adjusted so that the number density of the electroconductive particle in an anisotropic conductive film might be about 5000 piece / mm <2>.

Experimental Example 2

The anisotropic conductive film was produced and evaluated similarly to Experimental Example 1 except having changed the compounding quantity of the insulating filler to 0.15g (23.5 volume% with respect to the electrically-conductive particle), and manufactured the anisotropic conductive adhesive agent.

Experimental Example 3

The anisotropic conductive film was produced and evaluated similarly to Experimental Example 1 except having changed the compounding quantity of an insulating filler to 0.05 g (7.8 volume% with respect to electrically conductive particle), and manufactured the anisotropic conductive adhesive.

Experimental Example 4

Except having manufactured the anisotropic conductive adhesive agent without mix | blending an insulating filler, it carried out similarly to Experimental example 1, and produced the anisotropic conductive film, and evaluated.

Experimental Example 5

Anisotropic conductive films were prepared in the same manner as in Experimental Example 1 except that the compounding amount of the insulating filler was changed to 1 g (156 vol% based on the conductive particles) to prepare an anisotropic conductive adhesive, and evaluation was performed.

Experimental Example 6

The anisotropic conductive film was produced and evaluated similarly to Experimental Example 1 except having changed the compounding quantity of an insulating filler to 0.01g (1.56 volume% with respect to electroconductive particle), and manufactured the anisotropic conductive adhesive.

[With or without insulating filler]

The cross section of the electroconductive particle in an anisotropic conductive film was observed with the scanning electron microscope, and it was confirmed whether the insulating filler adhered to the surface of the electroconductive particle. The case where the insulating filler adhered to the surface of the electroconductive particle was evaluated as "yes", and the case where it was not attached was evaluated as "nothing". The results are shown in Table 1.

[Difference in Number Density of Conductive Particles]

The number density of the conductive particles of the entire anisotropic conductive film (1.0 mm × 1.0 mm) (number / mm 2) and the number density of the conductive particles in the 0.2 mm × 0.2 mm region arbitrarily extracted 10 points from the anisotropic conductive film ( Pieces / mm 2) was evaluated. Evaluation criteria are shown below. A or B is preferred. The results are shown in Table 1. In addition, the difference of number density is the difference of the maximum value and minimum value of the number density of the electroconductive particle in the predetermined area | region extracted arbitrarily.

A: Number density difference is 10% or less

B: Number density difference is larger than 10% and 15% or less

C: number density difference is more than 15% (greater than)

[Manufacture of bonded structure]

A flexible substrate (copper wiring: line / space (L / S) = 25 µm / 25 µm, terminal height: 8 µm, polyimide thickness: 25 µm), and ITO beta glass (thickness: 0.7 mm) were manufactured. Using the electrically conductive film, it heated and pressurized (180 degreeC, 2 Mpa, 20 second) with the heating press member, and obtained the bonded structure.

[Initial resistance value]

Using the digital multimeter (manufactured by Yokogawa Electric Co., Ltd.), the conduction resistance value of the connected structure when a current of 1 mA was flown by the four-terminal method was measured. The evaluation whose conduction resistance value of a bonded structure is less than 2.0 ohms was made into "OK", and the evaluation whose conduction resistance value is 2.0 ohms or more was made into "NG". In Experimental Examples 1-3, all were OK.

[Resistance value after connection reliability test]

After leaving a bonded structure at 60 degreeC and the atmosphere of 95% of a relative humidity for 1000 hours, the conduction resistance value of this bonded structure was measured by the method similar to an initial stage resistance value. Evaluation criteria made evaluation of less than 5.0 ohms "OK", and made the evaluation of conduction resistance value 5.0 ohms or more "NG". In Experimental Examples 1-3, all were OK.

[Conductive Particle Capture]

About the bonded structure sample, it confirmed that the sufficient number was captured by Experimental Examples 1-3 with respect to the electroconductive particle number captured by the opposing terminal. Moreover, when the capture | acquisition state was compared in Experimental Examples 1-3 and Experimental Examples 4-6, Experimental Examples 1-3 showed the uniform tendency of the number of capture | acquisition in each bump.

[short]

The same bonded structure used in the evaluation of the initial resistance value was manufactured, and the presence or absence of short generation between adjacent terminals was evaluated. The evaluation when a shot incidence rate is 50 ppm or less was made into "OK", and the evaluation when a shot incidence rate exceeded 50 ppm was made into "NG". In Experimental Examples 1-3, all were OK.

In Experimental Examples 1-3, the amount of the insulating filler whose particle diameter is 0.02% or more and 5.0% or less of the particle diameter with respect to electroconductive particle was made more than 1.56 volume% and less than 156 volume%, and by stirring a conductive particle and an insulating filler, It was found that the difference in the number density of the conductive particles (second coated conductive particles) in the anisotropic conductive film can be made small. In particular, it can be seen from Experimental Examples 1 to 3 that a favorable state can be obtained by setting it to 7.8 to 78.2% by volume. That is, it was found that the dispersibility of the conductive particles is good.

In Experimental Examples 1-3, SEM image observation of the electroconductive particle in a film cross section was performed, and the coating | coating state of the insulating filler was confirmed. In addition, in the 2nd covering electroconductive particle in the insulating binder obtained in this way, a part of coating | cover of an insulating filler may remain. Remaining | survival of the coating | cover of the insulating filler on the surface of this electrically conductive particle was confirmed from the observation by the electron microscope (SEM) of the 2nd coating conductive particle which concerns on Experimental Examples 1-3.

Moreover, in Experimental Examples 1-3, it turned out that the short between the electrode terminals of an electronic component can be suppressed. Moreover, in Experimental Examples 1-3, it turned out that the electroconductive particle capture | acquisition rate is favorable and evaluation of the resistance value after initial stage resistance value and the reliability test was also favorable. Moreover, in Experimental example 1 and 2, it turned out especially that the dispersibility of electroconductive particle is more favorable.

In Experimental Example 4 in which the particle diameter was not blended with an insulating filler having 0.02 to 5.0% of the particle size of the conductive particles, it was found that the difference in the number density of the conductive particles could not be reduced. That is, in Experimental Example 4, it was found that the dispersibility of the conductive particles was not good. In addition, in Experimental Example 4, it was found that the short between the electrode terminals of the electronic component could not be suppressed and that the conductive particle capture ratio was not good. Moreover, in Experimental Example 4, it turned out that evaluation of the initial stage resistance value and the resistance value after a reliability test was not favorable compared with Examples 1-3.

In Experimental Example 5 in which the amount of the insulating filler having a particle size of 0.02 to 0.5% of the particle size of the conductive particles with respect to the conductive particles was 156% by volume, it was found that the difference in the number density of the conductive particles could not be reduced. That is, in Experimental Example 5, since the number ratio of the insulating filler whose particle diameter is 0.02 to 0.5% of the particle diameter of electroconductive particle was excessive, it turned out that the dispersibility of electroconductive particle is not favorable. Moreover, in Experimental Example 5, it turned out that the short between the electrode terminals of an electronic component cannot be suppressed, and the electroconductive particle capture rate is not favorable. Moreover, in Experimental Example 5, compared with Examples 1-3, it turned out that evaluation of the initial stage resistance value and the resistance value after a reliability test was neither favorable.

In Experimental Example 6 in which the amount of the insulating filler having a particle size of 0.02 to 0.5% of the particle size of the conductive particles to 1.57% by volume with respect to the conductive particles, it was found that the difference in the number density of the conductive particles could not be reduced. That is, in Experimental Example 6, it was found that the dispersibility of the conductive particles was not good because the ratio of the number of the insulating fillers having the particle diameter of 0.02 to 0.5% of the particle diameter of the conductive particles was insufficient. Moreover, in Experimental Example 6, compared with Examples 1-3, the short between the electrode terminals of an electronic component was not able to be suppressed, and it turned out that the electroconductive particle capture rate is not favorable.

Hereinafter, a second embodiment of the present technology will be described.

Example 1

[Production of Anisotropic Conductive Adhesive]

1 g of conductive particles (Au plating (outer layer, thickness 34 nm) / Ni plating (inner layer, thickness 200 nm), resin core, specific gravity 1.4 g / cm 3) having an average particle diameter of 20 μm and an insulating filler having an average particle diameter of 10 nm 0.5 g (38.7% by volume of conductive particles) of a silica filler (product name: YA010C, specific gravity 2.2 g / cm 3) was added to a planetary stirring device (product name: manufactured by THINKY Co., Ltd.), and stirred for 5 minutes. Thus, a mixture of conductive particles and insulating filler was prepared.

About the ratio of the number of insulating fillers, it evaluated with "suitable quantity", "excess", and "lack". Specifically, the case where the number ratio of the silica filler to the conductive particles, that is, the amount of the silica filler to the conductive particles is in the range of 0.78 to 77% by volume was evaluated as "appropriate amount". Moreover, when the quantity of the silica filler with respect to electroconductive particle exceeded 77 volume%, it evaluated as "excess." In addition, the case where the quantity of the silica filler with respect to electroconductive particle is less than 0.78 volume% was evaluated as "lack".

A mixture of the conductive particles and the insulating filler and an insulating binder composed of the following components were added to a planetary stirring device (product name: Awatori Renta, manufactured by THINKY), and stirred for 1 minute to prepare an anisotropic conductive adhesive.

The insulating binder is an epoxy resin (EP828: manufactured by Mitsubishi Chemical Corporation); 20 g and phenoxy resin (YP-50: manufactured by Shinnitetsu Sumkin Chemical Co., Ltd.); 30 g and a curing agent (Novacure 3941HP, manufactured by Asahi Chemical Co., Ltd.); 50 g of which was diluted with toluene and mixed was used.

[Production of Anisotropic Conductive Film]

The anisotropic conductive adhesive was apply | coated on PET film, it dried for 5 minutes in 80 degreeC oven, and the adhesion layer which consists of an anisotropic conductive adhesive was formed on PET film. This obtained the 25-micrometer-thick anisotropic conductive film. In addition, it adjusted so that the number density of the electroconductive particle in an anisotropic conductive film might be about 300 piece / mm <2>.

[With or without insulating filler]

The cross section of the electroconductive particle in an anisotropic conductive film was observed with the scanning electron microscope, and it was confirmed whether the insulating filler adhered to the surface of the electroconductive particle. The case where the insulating filler adhered to the surface of the electroconductive particle was evaluated as "yes", and the case where it was not attached was evaluated as "nothing". The results are shown in Table 2.

[Difference in Number Density of Conductive Particles]

The number density of the conductive particles of the entire anisotropic conductive film (1.0 mm × 1.0 mm) (number / mm 2) and the number density of the conductive particles in the 0.2 mm × 0.2 mm region arbitrarily extracted 10 points from the anisotropic conductive film ( Pieces / mm 2) was evaluated. Evaluation criteria are shown below. A or B is preferred. In addition, the difference of number density is the difference of the maximum value and minimum value of the number density of the electroconductive particle in the predetermined area | region extracted arbitrarily. The results are shown in Table 2.

A: Number density difference is 10% or less

B: Number density difference is larger than 10% and 15% or less

C: number density difference is more than 15% (greater than)

[Manufacture of bonded structure]

Flexible substrate (copper wiring: line / space (L / S) = 100 µm / 100 µm, terminal height: 12 µm, polyimide thickness: 25 µm), and alumina ceramic substrate (gold / tungsten wiring: line / space ( L / S) = 100 µm / 100 µm, wiring height: 10 µm, substrate thickness: 0.4 mm, using a manufactured anisotropic conductive film, heat pressurization (180 ° C, 1 MPa, 20 seconds) with a heating press member ) To obtain a bonded structure.

[Initial resistance value]

Using the digital multimeter (manufactured by Yokogawa Electric Co., Ltd.), the conduction resistance value of the connected structure when a current of 1 mA was flown by the four-terminal method was measured. The evaluation whose conduction resistance value of a bonded structure is less than 1.0 ohm was made into "OK", and the evaluation whose conduction resistance value is 1.0 ohm or more was made into "NG". The results are shown in Table 2.

[Resistance value after connection reliability test]

After leaving a bonded structure at 60 degreeC and the atmosphere of 95% of a relative humidity for 1000 hours, the conduction resistance value of this bonded structure was measured by the method similar to an initial stage resistance value. Evaluation criteria were made the same as the initial resistance value. The results are shown in Table 2.

[Conductive Particle Capture]

About the bonded structure sample, the number of the electroconductive particle captured by the opposing terminal was counted, the average value of the number of electroconductive particle captured by the total number of terminal 150 was calculated | required, and this average value was evaluated based on the following references | standards. Evaluation criteria are shown below. A or B is preferred. The results are shown in Table 2.

A: 5 or more

B: 3-4 pieces

C: less than 2

[short]

The same bonded structure used in the evaluation of the initial resistance value was manufactured, and the presence or absence of short generation between adjacent terminals was evaluated. The evaluation when a shot incidence rate is 50 ppm or less was made into "OK", and the evaluation when a shot incidence rate exceeded 50 ppm was made into "NG". The results are shown in Table 2.

Example 2

The anisotropic conductive film was produced and evaluated similarly to Example 1 except having changed the compounding quantity of the insulating filler to 0.15g (11.6 volume% with respect to the electrically-conductive particle), and manufactured the anisotropic conductive adhesive agent.

Example 3

The anisotropic conductive film was produced and evaluated similarly to Example 1 except having changed the compounding quantity of the insulating filler to 0.05g (3.9 volume% with respect to the electrically-conductive particle), and manufactured the anisotropic conductive adhesive agent.

Comparative Example 1

Except having manufactured the anisotropic conductive adhesive agent without mix | blending an insulating filler, it carried out similarly to Example 1, and produced the anisotropic conductive film and evaluated.

Comparative Example 2

The anisotropic conductive film was produced and evaluated similarly to Example 1 except having changed the compounding quantity of the insulating filler to 1.0g (77.3 volume% with respect to the electrically-conductive particle), and manufactured the anisotropic conductive adhesive agent.

Comparative Example 2

The anisotropic conductive film was produced and evaluated similarly to Example 1 except having changed the compounding quantity of an insulating filler into 0.01g (0.77 volume% with respect to the electrically-conductive particle), and manufactured the anisotropic conductive adhesive agent.

In Examples, the conductivity in the anisotropic conductive film is obtained by stirring the conductive particles and the insulating filler with the amount of the insulating filler having a particle size of 0.02 to 0.143% of the particle size of the conductive particles to 0.78 to 77% by volume with respect to the conductive particles. It turned out that the difference of the number density of particle | grains (2nd covering electroconductive particle) can be made small. In particular, it can be seen from the examples that a favorable state can be obtained by using 3.9 to 38.7% by volume. That is, it was found that the dispersibility of the conductive particles is good. Moreover, in the Example, it turned out that the short between the electrode terminals of an electronic component can be suppressed. Moreover, in the Example, it turned out that the electroconductive particle capture rate is favorable and evaluation of the resistance value after initial stage resistance value and the reliability test was also favorable. In particular, in Examples 1 and 2, it turned out that the dispersibility of electroconductive particle is more favorable.

In the Example, the 1st coating electroconductive particle 10 is obtained as shown in FIG. 2 by stirring electroconductive particle and an insulating filler. And by stirring the 1st coating conductive particle 10 in an insulating binder, a silica filler isolate | separates from the conductive particle in the 1st coating conductive particle 10, and as shown in FIG. 3, the 2nd coating conductive particle 11 ) Is obtained. In addition, the separated silica filler is interposed between the second coated conductive particles 11. Thereby, aggregation of the 2nd covering electroconductive particle 11 is suppressed and the 2nd covering electroconductive particle 11 can be disperse | distributed uniformly in an insulating binder. In addition, in the 2nd covering electroconductive particle 11 in the insulating binder obtained in this way, a part of coating | cover of an insulating filler may remain. Remaining | survival of the coating | cover of the insulating filler on the surface of this electroconductive particle was confirmed from observation by the electron microscope (SEM) of the 2nd coating electroconductive particle 11 which concerns on Examples 1-3.

In Comparative Example 1 in which the particle diameter was not blended with an insulating filler having 0.02 to 0.143% of the particle size of the conductive particles, it was found that the difference in the number density of the conductive particles could not be reduced. That is, in Comparative Example 1, it was found that the dispersibility of the conductive particles was not good. Moreover, in the comparative example 1, it turned out that the short between the electrode terminals of an electronic component cannot be suppressed, and the electroconductive particle capture rate is not favorable. In the comparative example 1, as shown in FIG. 4, by using the electrically-conductive particle (raw particle) 12 which is not coat | covered with the silica filler, as shown in FIG. 5, the some electrically-conductive particle 12 in an insulating binder is shown. ) Are linked and aggregated.

In Comparative Example 2 in which the amount of the insulating filler having a particle size of 0.02 to 0.143% of the particle size of the conductive particles to the conductive particles was 77.3% by volume (greater than 77% by volume), the difference in the number density of the conductive particles cannot be made small. I could see that. That is, in the comparative example 2, since the number ratio of the insulating filler whose particle diameter is 0.02 to 0.143% of the particle diameter of electroconductive particle was excessive, it turned out that the dispersibility of electroconductive particle is not favorable. Moreover, in the comparative example 2, it turned out that the short between the electrode terminals of an electronic component cannot be suppressed, and the electroconductive particle capture rate is not favorable. Moreover, in the comparative example 2, it turned out that evaluation of the initial stage resistance value and the resistance value after a reliability test was neither favorable. In the comparative example 2, after mixing electrically conductive particle and a silica filler, it turned out that the coating electrically-conductive particle 13 in which two electrically conductive particles were coat | covered with the silica filler was formed, for example as shown in FIG.

In Comparative Example 3 in which the amount of the insulating filler having a particle size of 0.02 to 0.143% of the particle size of the conductive particles relative to the conductive particles was 0.77% by volume (less than 0.78% by volume), the difference in the number density of the conductive particles cannot be made small. I could see that. That is, in the comparative example 3, since the number ratio of the insulating filler which is 0.02 to 0.143% of the particle diameter of the conductive particle was insufficient, it turned out that the dispersibility of electrically conductive particle is not favorable. Moreover, in the comparative example 3, it turned out that the short between the electrode terminals of an electronic component cannot be suppressed, and the electroconductive particle capture rate is not favorable.

1: connection structure
2: anisotropic conductive film
3: conductive particles
4: first terminal string
5: the first electronic component
6: second terminal string
7: second electronic components
10: first covering conductive particles
11: second coating conductive particles
12: conductive particles
13: coated conductive particles
20: some coated particles
21: large diameter particle
22: covering part
23: exposed part

Claims (23)

It contains the coated large diameter particle | grains in which one part of the surface of the large diameter particle was coat | covered by the small particle diameter filler, the small particle diameter filler, and an insulating binder,
The coated large diameter particles are dispersed and
The particle diameter of the said large diameter particle is 2 micrometers or more,
The particle diameter of the said small particle diameter filler is 0.02% or more and 5.0% or less of the particle diameter of the said large diameter particle | grains,
The resin composition whose quantity of the said small particle diameter filler with respect to the said large diameter particle | grains is less than 156 volume%. The method of claim 1,
The resin composition, wherein the large diameter particles are conductive particles. The method according to claim 1 or 2,
The resin composition, wherein the small particle filler is a silica filler. The method according to any one of claims 1 to 3,
The resin composition whose particle diameter of the said large diameter particle | grains is less than 50 micrometers. The process of obtaining the 1st coating particle by which the said large diameter particle was coat | covered by the said small particle diameter filler by stirring the large diameter particle whose average particle diameter is 2 micrometers or more, and the small particle diameter filler whose particle diameter is 0.02% or more and 5.0% or less of the particle diameter of the said large diameter particle. (A) Wow,
By stirring the said 1st coating particle and an insulating binder, the 2nd coating particle which a part of the surface of the said large diameter particle was coat | covered with the said small particle diameter has the process (B) which obtains the resin composition disperse | distributed in the said insulating binder. ,
In the said process (A), the said large diameter particle and the said small particle diameter filler are mix | blended so that the quantity of the said small particle size filler with respect to the said large diameter particle may be less than 156 volume%. The adhesive agent which consists of a resin composition in any one of Claims 1-4. The adhesive film which consists of an adhesive agent of Claim 6. The method of claim 7, wherein
The difference of the number density (piece / mm <2>) of the said large-diameter particle | grains of the whole said adhesive film, and the number density (piece / mm <2>) of the said large diameter particle in the area | region of 0.2 mmx0.2 mm extracted arbitrarily from the said adhesive film is 15% or less , Adhesive film. An anisotropic conductive adhesive consisting of the resin composition according to any one of claims 1 to 4, wherein the large diameter particles are conductive particles. The anisotropic conductive film which consists of an anisotropic conductive adhesive of Claim 9. The structure by which the 1st member and the 2nd member were connected through the adhesive agent of Claim 6, or the adhesive film of Claim 7. The connection structure in which the 1st electronic component and the 2nd electronic component were anisotropically connected through the anisotropic conductive adhesive agent of Claim 9, or the anisotropic conductive film of Claim 10. The manufacturing method of the structure which connects a 1st member and a 2nd member through the adhesive agent of Claim 6, or the adhesive film of Claim 7. The manufacturing method of the bonded structure which anisotropically connects a 1st electronic component and a 2nd electronic component via the anisotropic conductive adhesive agent of Claim 9, or the anisotropic conductive film of Claim 10. Contains coated conductive particles, part of the surface of the conductive particles covered by the insulating filler, an insulating filler, and an insulating binder,
The said coating conductive particle is disperse | distributed in the said insulating binder,
The particle diameter of the said electroconductive particle is 7 micrometers or more,
The particle diameter of the said insulating filler is 0.02 to 0.143% of the particle diameter of the said electroconductive particle,
The anisotropic conductive adhesive agent whose quantity of the said insulating filler with respect to the said electroconductive particle is 0.78-77 volume%. The method of claim 15,
The said insulating filler is a silica filler. The method according to claim 15 or 16,
Anisotropic conductive adhesive whose particle diameter of the said electroconductive particle is 50 micrometers or less. The anisotropic conductive film which consists of an anisotropic conductive adhesive in any one of Claims 15-17. The method of claim 18,
Of the number density (pieces / mm 2) of the coated conductive particles of the entire anisotropic conductive film and the number density (pieces / mm 2) of the coated conductive particles in a 0.2 mm × 0.2 mm region arbitrarily extracted from the anisotropic conductive film. Anisotropic conductive film whose difference is 15% or less. A step of obtaining first coated conductive particles coated with the conductive particles by the insulating filler by stirring the conductive particles having an average particle diameter of 7 µm or more and the insulating filler having a particle diameter of 0.02 to 0.143% of the particle diameter of the conductive particles (A ) Wow,
By stirring the said 1st coating conductive particle and an insulating binder, the process (B) which the 2nd coating conductive particle by which the part of the surface of the said conductive particle was coat | covered with the said insulating filler obtains the anisotropic conductive adhesive dispersed in the said insulating binder. With
In the said process (A), the manufacturing method of the anisotropic conductive adhesive which mix | blends the said electroconductive particle and the said insulating filler so that the quantity of the said insulating filler with respect to the said electroconductive particle may be 0.78-77 volume%. The connection structure in which the 1st electronic component and the 2nd electronic component were anisotropically connected through the anisotropic conductive adhesive of any one of Claims 15-17, or the anisotropic conductive film of Claim 18. The method of claim 21,
The connection structure according to claim 1, wherein the first electronic component or the second electronic component is a ceramic substrate. The manufacturing method of the bonded structure which anisotropically connects a 1st electronic component and a 2nd electronic component via the anisotropic conductive adhesive agent in any one of Claims 15-17, or the anisotropic conductive film of Claim 18.

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