JP3622927B2

JP3622927B2 - Anisotropic conductive film

Info

Publication number: JP3622927B2
Application number: JP24899294A
Authority: JP
Inventors: 幸男山田; 尚安藤; 保博須賀; 博行熊倉; 博之熊倉
Original assignee: Sony Chemicals Corp
Current assignee: Dexerials Corp
Priority date: 1994-10-14
Filing date: 1994-10-14
Publication date: 2005-02-23
Also published as: JPH08115617A

Description

【０００１】
【産業上の利用分野】
本発明は、いわゆるＴＡＢ型の端子等の電気的、機械的接続に用いられる異方性導電膜に関するものである。
【０００２】
【従来の技術】
例えば、液晶表示装置においては、図１に示すように、液晶表示装置（ＬＣＤ）１の電極２とテープ・オートメイテッド・ボンディング型（ＴａｐｅＡｕｔｏｍａｔｅｄＢｏｎｄｉｎｇ型、以下、ＴＡＢ型と称する。）の端子板３の電極４間を接続するのに、異方性導電膜５を使用している。
【０００３】
上記異方性導電膜５は、例えばウレタン，ポリエステル，クロロプレン等の熱可塑性のホットメルト樹脂或いはエポキシ等の熱硬化性樹脂等よりなる絶縁性接着剤６中に、平均粒径が１０μｍ程度であり、ニッケル，金，半田等の金属粒子或いはスチレン樹脂等よりなる粒子表面をニッケル−金等の導電層により被覆した粒子等の導通のための導通用粒子７が分散されたものである。
【０００４】
これを用いて液晶表示装置１の電極２とＴＡＢ型端子板３の電極４の接続を行う場合には、先ず、図１に示すように、上記電極２，４間に異方性導電膜５を挟むようにして配する。
【０００５】
そして、例えば絶縁性接着剤６として熱可塑性のホットメルト樹脂を使用している場合には、加熱を行って異方性導電膜５の絶縁性接着剤６を溶融させるとともに液晶表示装置１とＴＡＢ型端子板３を圧接させる。
【０００６】
すると、異方性導電膜５内の導通用粒子７が電極２，４間に潰されるような形で挟み込まれ、電極２，４間の接続が行われ、導通がなされることとなる。
【０００７】
続いて冷却を行い、絶縁性接着剤６を固化して電極２，４間の導通を保った状態で液晶表示装置１とＴＡＢ型端子板３間を接着する。
【０００８】
なお、上記のような異方性導電膜により液晶表示装置とＴＡＢ型端子板の電極間を接続した場合、上記接続が確実に行われているかどうかの接続状態の良否の判定は以下のようにして行っている。すなわち、通常、液晶表示装置はガラスよりなり、ＴＡＢ型端子板の電極がＩＴＯ膜よりなることから、これらを透かして電極間に潰されるような形で挟み込まれた導通用粒子の数を顕微鏡等により確認して行っている。
【０００９】
ところで、近年においては、液晶表示装置或いはＴＡＢ型端子板上における電極間の間隔、すなわちピッチが小さくなってきており、上記のような平均粒径が１０μｍ程度の導通用粒子を用いた異方性導電膜を用いると、導通用粒子が大き過ぎて、隣接する電極間にまたがり、これらを接続してしまい、ショート等が発生するという不都合が生じている。
【００１０】
そこで、異方性導電膜に用いる導通用粒子として平均粒径５±０．１μｍ程度の大きさのものを使用するようになってきている。上記導通用粒子としては、ジビニルベンゼン，ベンゾグアナミン等よりなる粒子表面に導電層を設けたものが挙げられる。
【００１１】
【発明が解決しようとする課題】
しかしながら、上記のように導通用粒子の平均粒径が５±０．１μｍ程度と小さいと、導通用粒子の変形の確認が難しく、上述のような方法で接続状態の良否の判定を行うことは難しい。また、導通用粒子として、ジビニルベンゼン，ベンゾグアナミン等よりなる粒子表面に導電層を設けたものを用いた場合、導通用粒子の固さが固く、その変形を確認することはさらに困難となる。
【００１２】
そこで本発明は、従来の実情に鑑みて提案されたものであり、電極間に挟み込まれた導通用粒子が小さくても、接続状態の良否の判定が簡便に行われる異方性導電膜を提供することを目的とする。
【００１３】
【課題を解決するための手段】
上述の目的を達成するための本発明の異方性導電膜は、絶縁性接着剤中に導通のための導通用粒子と接続状態の良否判定のための良否判定用粒子とが分散されており、良否判定用粒子の１０％変位時における圧縮強度が、導通用粒子の１０％圧縮強度よりも小さく、導通用粒子の平均粒径が３〜１０μｍであり、良否判定用粒子の平均粒径が５μｍを超え、且つ導通用粒子の平均粒径の１．２５〜４倍であり、良否判定用粒子１重量部に対して導通用粒子が１０〜２０重量部配合されていることを特徴とするものである。
【００１４】
また、上述の圧縮強度は、粒子に圧縮を行い、その直径が１０％変形したときの荷重を調査し、下記式１により算出するものである。
【００１５】
Ｓｔ＝２．８Ｐ／π・ｄ^２・・・（式１）
なお、上記式１中Ｓｔは圧縮強度を示し、Ｐは１０％変形したときの荷重を示し、ｄは粒子の直径を示す。
【００１６】
さらに、本発明の異方性導電膜においては、導通用粒子及び良否判定用粒子は、ニッケルで被覆されたジビニルベンゼンを金メッキした粒子であることが好ましい。
【００１７】
【作用】
本発明の異方性導電膜においては、絶縁性接着剤中に導通のための導通用粒子と接続状態の良否判定のための良否判定用粒子とが分散されており、良否判定用粒子の１０％変位時における圧縮強度が、導通用粒子の１０％圧縮強度よりも小さく、導通用粒子の平均粒径が３〜１０μｍであり、良否判定用粒子の平均粒径が５μｍを超え、且つ導通用粒子の平均粒径の１．２５〜４倍であり、良否判定用粒子１重量部に対して導通用粒子が１０〜２０重量部配合されているため、これを用いて電極間等の接続を行った場合、良否判定用粒子の方が導通用粒子よりも先に潰れ、良否判定用粒子の確認が容易となるとともに、良否判定用粒子が導通用粒子の電極間の接続を妨げることもない。
【００１８】
【実施例】
以下、本発明の好適な実施例について実験結果に基づいて説明する。
【００１９】
先ず、試料の製造を行った。すなわち、絶縁性接着剤として、フェノキシ樹脂（ＹＰ５０：商品名、東都化成社製）４０重量部とエポキシ樹脂（ＥＰ８２８：商品名、油化シェル社製）３０重量部と潜在性硬化剤（ＨＸ３７４１：商品名、旭化成社製）３０重量部を混合したものを用意し、これに表１及び表２中に示すような粒子をそれぞれ混入させて実施例１〜３及び比較例１〜１１を製造した。
【００２０】
【表１】

【００２１】
【表２】

【００２２】
なお、表１，２中の数字はそれぞれ重量部を示し、粒子Ａはベンゾグアナミンに金メッキを行ったブライト２０ＧＮＲ４．６ＥＨ（商品名、日本化学工業社製）の平均粒径４．６μｍのものであり、粒子Ｂはジビニルベンゼンにニッケル／金メッキを行ったミクロパールＡｕ２１０（商品名、積水ファインケミカル社製）の平均粒径５．０μｍのものであり、粒子Ｃはジビニルベンゼンにニッケル／金メッキを行ったミクロパールＡｕ２０５２５（商品名、積水ファインケミカル社製）の平均粒径１０．０μｍのものであり、粒子Ｄは粒子Ｃと同一商品の平均粒径が５．０μｍのものであり、粒子Ｅは粒子Ｂと同一商品の平均粒径が１１．０μｍのものであり、粒子Ｆは粒子Ｂと同一商品の平均粒径が２．５μｍのものであり、粒子Ｇは粒子Ｂと同一商品の平均粒径が３．０μｍのものであり、粒子Ｉは粒子Ｃと同一商品の平均粒径が２５μｍのものであり、粒子Ｊは粒子Ｃと同一商品の平均粒径が１５μｍのものであり、粒子Ｋは１０％架橋スチレン粒子を金メッキしたものの平均粒径が７．５μｍ（粒径分布：４〜１２μｍ）のものである。
【００２３】
また、これら粒子Ａ〜Ｋの１０％変位時における圧縮強度を各粒子の平均粒径と併せて表３に示す。なお、上記圧縮強度は島津製作所社製の微小圧縮試験機ＭＣＴＭ−２００（機種名）を用い、圧縮試験モードで、試験荷重３．００ｇｆで、負荷速度定数２（０．１３５ｇｆ／ｓｅｃ）で、変位スケール５．００（μｍ）で、圧子５０（μｍφ）の条件下で測定した。
【００２４】
【表３】

【００２５】
次に、上記実施例１〜３及び比較例１〜１１を剥離フィルム上に厚さが２０μｍとなるようにコーティングして異方性導電膜を製造した。なお、実施例１〜３及び比較例１〜１１を用いた異方性導電膜を便宜上、それぞれ実施例１〜３及び比較例１〜１１と称することとする。
【００２６】
そして、上記実施例１〜３及び比較例１〜１１の異方性導電膜を用い、厚さ７５μｍのポリイミド（ユーピレックス：商品名、宇部興産社製）よりなる基材上に厚さ２５μｍの錫メッキされた銅パターンをパターン間のピッチが７０μｍとなるように形成したＴＡＢ型端子板とＩＴＯ膜よりなる電極が一面に形成されたガラス間の接続を行った。なお、上記接続は温度１６０℃で３０ｋｇ／ｃｍ^２の圧力を１５秒間加えて行った。
【００２７】
続いて、上記のように実施例１〜３及び比較例１〜１１の異方性導電膜を用いて接着を行ったＴＡＢ型端子板とＩＴＯ膜よりなる電極間の導通、ＴＡＢ型端子板の隣接する２つのピン間における絶縁、接着状態の良否について調査した。
【００２８】
上記導通は初期の導電性と８５℃，８５ＲＨ％の条件下で１０００時間放置した後の導電性について調査し、初期においては５Ω以下を○として評価し、１０Ω以上を×として評価し、放置後においては１０Ω以下を○として評価し、５０Ω以上を×として評価した。
【００２９】
また、上記絶縁は１０^８Ω以上を○として評価し、１０^８Ω未満を×として評価した。
【００３０】
さらに、接着状態の良否は５０倍の光学顕微鏡を用いて観察を行った場合に判定が可能かどうかを評価し、可能である場合を○として評価し、不可能である場合を×として評価した。実施例１〜３の結果を表４に示し、比較例１〜１１の結果を表５に示す。
【００３１】
【表４】

【００３２】
【表５】

【００３３】
表４の結果を見てわかるように、各々の異方性導電膜中における接続状態の良否判定用粒子（粒子Ｃ）の１０％変位時における圧縮強度が、導通用粒子（粒子Ｂ，Ｇ）の１０％変位時における圧縮強度よりも小さく、良否判定用粒子（粒子Ｃ）の粒径が導通用粒子（粒子Ｂ，Ｇ）の粒径よりも大きく、良否判定用粒子（粒子Ｃ）の平均粒径が５μｍ以上であり、且つ導通用粒子（粒子Ｂ，Ｇ）の平均粒径の１．２５〜４倍であり、導通用粒子（粒子Ｂ，Ｇ）の平均粒径が３μｍ〜１０μｍであり、導通用粒子（粒子Ｂ，Ｇ）と良否判定用粒子（粒子Ｃ）の合計配合量が絶縁性接着剤１００重量部に対して１〜２０重量部であり、良否判定用粒子（粒子Ｃ）１重量部に対して導通用粒子（粒子Ｂ，Ｇ）が１０〜２０重量部配合されている実施例１〜３においては、各特性が良好なものとなっている。
【００３４】
一方、表５の結果を見てわかるように、比較例１，２においては導通用粒子（粒子Ａ，Ｂ）の平均粒径が小さく、また圧縮強度が大きいため、良否判定が困難である。また、比較例３においては、良否判定用粒子（粒子Ｅ）の圧縮強度が大きく潰れにくいため、導通用粒子（粒子Ｄ）がＴＡＢ型端子板とＩＴＯ膜よりなる電極間を導通することが困難であり、抵抗が高く、導通特性が低くなっている。さらに、比較例４においては、導通用粒子（粒子Ｆ）の粒径が小さすぎるためにＴＡＢ型端子板とＩＴＯ膜よりなる電極間の導通を確実に確保できず、導通特性が低くなっている。さらにまた、比較例５においては、良否判定用粒子（粒子Ｄ）の粒径が小さすぎるため良否の判定が困難である。
【００３５】
また、比較例６においては、良否判定用粒子（粒子Ｉ）の粒径が大きすぎるために絶縁特性が低くなっている。さらに、比較例７においては、導通用粒子（粒子Ｅ）の粒径が大きすぎて絶縁を阻害し、絶縁特性が低くなっている。さらにまた、比較例８においては、導通用粒子（粒子Ｋ）の粒度分布が広すぎるために絶縁を阻害し、絶縁特性が低くなっている。
【００３６】
また、比較例９においては、導通用粒子（粒子Ｂ）の配合量が多く、絶縁を阻害し、絶縁特性が低くなっている。さらに、比較例１０においては、良否判定用粒子（粒子Ｃ）の配合量が少なく、該良否判定用粒子を確認するのが困難であり、良否判定が困難となっている。さらにまた、比較例１１においては、良否判定用粒子（粒子Ｃ）の配合量が多く、絶縁を阻害し、絶縁特性が低くなっている。
【００３７】
【発明の効果】
以上の説明からも明らかなように、本発明の異方性導電膜においては、絶縁性接着剤中に導通のための導通用粒子と接続状態の良否判定のための良否判定用粒子とが分散されており、良否判定用粒子の１０％変位時における圧縮強度が、導通用粒子の１０％圧縮強度よりも小さく、導通用粒子の平均粒径が３〜１０μｍであり、良否判定用粒子の平均粒径が５μｍを超え、且つ導通用粒子の平均粒径の１．２５〜４倍であり、良否判定用粒子１重量部に対して導通用粒子が１０〜２０重量部配合されているため、これを用いて電極間等の接続を行った場合、良否判定用粒子の方が導通用粒子よりも先に潰れ、良否判定用粒子の確認が容易となり、接続状態の良否の判定が簡便に行われるとともに、良否判定用粒子が電極間の接続を妨げることもない。
【図面の簡単な説明】
【図１】液晶表示装置の一例を示す断面図である。
【符号の説明】
５異方性導電膜、６絶縁性接着剤、７導通用粒子[0001]
[Industrial application fields]
The present invention relates to an anisotropic conductive film used for electrical and mechanical connection of so-called TAB type terminals.
[0002]
[Prior art]
For example, in a liquid crystal display device, as shown in FIG. 1, an electrode 2 of a liquid crystal display device (LCD) 1 and a terminal board of a tape automated bonding type (Tape Automated Bonding type, hereinafter referred to as TAB type). An anisotropic conductive film 5 is used to connect the three electrodes 4.
[0003]
The anisotropic conductive film 5 has an average particle diameter of about 10 μm in an insulating adhesive 6 made of a thermoplastic hot melt resin such as urethane, polyester, chloroprene, or a thermosetting resin such as epoxy. Conductive particles 7 for conduction, such as particles in which the surface of particles made of metal particles such as nickel, gold, solder, or styrene resin is coated with a conductive layer such as nickel-gold, are dispersed.
[0004]
When using this to connect the electrode 2 of the liquid crystal display device 1 and the electrode 4 of the TAB type terminal board 3, first, as shown in FIG. Arrange them so that they are sandwiched.
[0005]
For example, when a thermoplastic hot melt resin is used as the insulating adhesive 6, the insulating adhesive 6 of the anisotropic conductive film 5 is melted by heating and the liquid crystal display device 1 and the TAB are used. The mold terminal board 3 is pressed.
[0006]
As a result, the conductive particles 7 in the anisotropic conductive film 5 are sandwiched between the

electrodes

2 and 4 so that the

electrodes

2 and 4 are connected to each other, thereby conducting electrical connection.
[0007]
Subsequently, cooling is performed, and the insulating adhesive 6 is solidified and the liquid crystal display device 1 and the TAB terminal board 3 are bonded together while the conduction between the

electrodes

2 and 4 is maintained.
[0008]
When the liquid crystal display device and the electrodes of the TAB type terminal plate are connected by the anisotropic conductive film as described above, whether the connection is reliable or not is determined as follows. Is going. That is, the liquid crystal display device is usually made of glass, and the electrodes of the TAB type terminal plate are made of an ITO film, so that the number of conductive particles sandwiched between the electrodes through these can be measured with a microscope or the like. Confirmed by.
[0009]
By the way, in recent years, the distance between electrodes on a liquid crystal display device or TAB type terminal plate, that is, the pitch has been reduced, and anisotropy using conductive particles having an average particle size of about 10 μm as described above. When the conductive film is used, the conductive particles are too large, span between adjacent electrodes, connect them, and a short circuit or the like occurs.
[0010]
Therefore, particles having an average particle size of about 5 ± 0.1 μm have been used as conductive particles used for the anisotropic conductive film. Examples of the conductive particles include those in which a conductive layer is provided on the particle surface made of divinylbenzene, benzoguanamine or the like.
[0011]
[Problems to be solved by the invention]
However, if the average particle size of the conductive particles is as small as about 5 ± 0.1 μm as described above, it is difficult to confirm the deformation of the conductive particles, and it is difficult to determine whether the connection state is good or not by the method described above. difficult. Further, when conductive particles having a conductive layer provided on the particle surface made of divinylbenzene, benzoguanamine or the like are used as the conductive particles, the conductive particles are hard and it is more difficult to confirm the deformation.
[0012]
Therefore, the present invention has been proposed in view of conventional circumstances, and provides an anisotropic conductive film that can easily determine whether a connection state is good or not even if the conductive particles sandwiched between the electrodes are small. The purpose is to do.
[0013]
[Means for Solving the Problems]
In the anisotropic conductive film of the present invention for achieving the above-described object, conductive particles for conduction and particles for quality determination for quality determination of a connected state are dispersed in an insulating adhesive. The compressive strength at the time of 10% displacement of the pass / fail judgment particles is smaller than the 10% compressive strength of the conducting particles, and the mean particle size of the conducting particles is 3 to 10 μm. More than 5 μm and 1.25 to 4 times the average particle size of the conductive particles, and 10 to 20 parts by weight of conductive particles are blended with 1 part by weight of the pass / fail judgment particles. Is.
[0014]
Moreover, the above-mentioned compressive strength is calculated by the following formula 1 after investigating the load when the particle is compressed and its diameter is deformed by 10%.
[0015]
St = 2.8P / π · d ² (Formula 1)
In the above formula 1, St represents the compressive strength, P represents the load when deformed by 10%, and d represents the particle diameter.
[0016]
Furthermore, in the anisotropic conductive film of the present invention, the conductive particles and the pass / fail judgment particles are preferably gold-plated divinylbenzene coated with nickel.
[0017]
[Action]
In the anisotropic conductive film of the present invention, the conductive particles for conduction and the quality determination particles for quality determination of the connection state are dispersed in the insulating adhesive. The compressive strength at% displacement is smaller than the 10% compressive strength of the conductive particles, the average particle size of the conductive particles is 3 to 10 μm, the average particle size of the pass / fail judgment particles exceeds 5 μm , and the conductive particles It is 1.25 to 4 times the average particle diameter of the particles, and 10 to 20 parts by weight of the conductive particles are blended with respect to 1 part by weight of the pass / fail judgment particles. In this case, the pass / fail judgment particles are crushed before the conduction particles, making it easier to check the pass / fail judgment particles, and the pass / fail judgment particles do not hinder the connection between the conduction particle electrodes. .
[0018]
【Example】
Hereinafter, preferred embodiments of the present invention will be described based on experimental results.
[0019]
First, a sample was manufactured. That is, as an insulating adhesive, 40 parts by weight of a phenoxy resin (YP50: trade name, manufactured by Toto Kasei Co., Ltd.), 30 parts by weight of an epoxy resin (EP828: trade name, manufactured by Yuka Shell Co., Ltd.) and a latent curing agent (HX3741: Examples 1 to 3 and Comparative Examples 1 to 11 were prepared by mixing 30 parts by weight (trade name, manufactured by Asahi Kasei Co., Ltd.) and mixing them with particles as shown in Table 1 and Table 2, respectively. .
[0020]
[Table 1]

[0021]
[Table 2]

[0022]
The numbers in Tables 1 and 2 indicate parts by weight, and the particles A are those of Bright 20GNR 4.6EH (trade name, manufactured by Nippon Chemical Industry Co., Ltd.) obtained by gold plating benzoguanamine and having an average particle diameter of 4.6 μm. Particle B is a micropearl Au210 (trade name, manufactured by Sekisui Fine Chemical Co., Ltd.) obtained by nickel / gold plating on divinylbenzene and having an average particle diameter of 5.0 μm. Pearl Au 20525 (trade name, manufactured by Sekisui Fine Chemical Co., Ltd.) has an average particle size of 10.0 μm, particle D has the same product as particle C and an average particle size of 5.0 μm, and particle E has particle B The average particle size of the same product is 11.0 μm, the particle F is the same product as the particle B and the average particle size is 2.5 μm, the particle G is the particle B Ri Der average particle diameter one product those 3.0 [mu] m, the particles I are those average particle diameter of the same product and particles C is 25 [mu] m, the particles J is the same product as the particles C average particle size 15μm of The particles K have a mean particle size of 7.5 μm (particle size distribution: 4 to 12 μm) obtained by gold-plating 10% crosslinked styrene particles.
[0023]
Table 3 shows the compressive strength at the time of 10% displacement of these particles A to K together with the average particle size of each particle. The above compressive strength is a compression test mode MCTM-200 (model name) manufactured by Shimadzu Corporation, with a test load of 3.00 gf and a load rate constant of 2 (0.135 gf / sec). The measurement was performed under the condition of a displacement scale of 5.00 (μm) and an indenter 50 (μmφ).
[0024]
[Table 3]

[0025]
Next, Examples 1 to 3 and Comparative Examples 1 to 11 were coated on a release film so as to have a thickness of 20 μm to produce an anisotropic conductive film. For convenience, the anisotropic conductive films using Examples 1 to 3 and Comparative Examples 1 to 11 are referred to as Examples 1 to 3 and Comparative Examples 1 to 11, respectively.
[0026]
And using the anisotropic conductive film of the said Examples 1-3 and Comparative Examples 1-11, 25 micrometers thick tin on the base material which consists of a polyimide (UPILEX: brand name, Ube Industries, Ltd.) of thickness 75 micrometers. A TAB type terminal plate formed by plating plated copper patterns so that the pitch between patterns was 70 μm and a glass having electrodes made of ITO films formed on one surface were connected. The connection was performed at a temperature of 160 ° C. and a pressure of 30 kg / cm ² was applied for 15 seconds.
[0027]
Subsequently, the conduction between the TAB terminal plate bonded with the anisotropic conductive films of Examples 1 to 3 and Comparative Examples 1 to 11 and the electrode made of the ITO film as described above, The quality of insulation and adhesion between two adjacent pins was investigated.
[0028]
The above continuity is investigated for the initial conductivity and the conductivity after being left for 1000 hours under the conditions of 85 ° C. and 85RH%. In the initial stage, 5Ω or less is evaluated as ○, 10Ω or more is evaluated as ×, In the evaluation, 10Ω or less was evaluated as ○, and 50Ω or more was evaluated as ×.
[0029]
In addition, the above-mentioned insulation was evaluated by evaluating 10 ⁸ Ω or more as ◯, and evaluating less than 10 ⁸ Ω as x.
[0030]
Furthermore, whether the adhesion state is good or not was evaluated by observing using a 50 × optical microscope. The evaluation was made as ◯ when it was possible, and was evaluated as x when it was impossible. . The results of Examples 1 to 3 are shown in Table 4, and the results of Comparative Examples 1 to 11 are shown in Table 5.
[0031]
[Table 4]

[0032]
[Table 5]

[0033]
As can be seen from the results in Table 4, the compressive strength at 10% displacement of the particles for determining pass / fail in each anisotropic conductive film (particles C) is determined to be conductive particles (particles B and G). less than the compressive strength at 10% displacement, greater than the particle size of the particle size conductive particles for quality determination particles (particles C) (particle B, G), the average of the quality determination particles (particles C) The particle size is 5 μm or more, and is 1.25 to 4 times the average particle size of the conductive particles (particles B and G), and the average particle size of the conductive particles (particles B and G) is 3 μm to 10 μm. Yes, the total blending amount of the conductive particles (particles B and G) and the quality determination particles (particle C) is 1 to 20 parts by weight with respect to 100 parts by weight of the insulating adhesive, and the quality determination particles (particle C). ) conducting particles (particles B with respect to 1 part by weight, carried G) is 10 to 20 parts by weight formulation example 1 In ~ 3, each characteristic is favorable.
[0034]
On the other hand, as can be seen from the results in Table 5, in Comparative Examples 1 and 2, since the average particle diameter of the conductive particles (particles A and B) is small and the compressive strength is large, it is difficult to determine pass / fail. Further, in Comparative Example 3, since the compressive strength of the pass / fail judgment particles (particle E) is large and difficult to be crushed, it is difficult for the conductive particles (particle D) to conduct between the TAB terminal plate and the electrode made of the ITO film. The resistance is high and the conduction characteristics are low. Furthermore, in Comparative Example 4, since the particle size of the conductive particles (particles F) is too small, conduction between the TAB terminal plate and the electrode made of the ITO film cannot be ensured reliably, and the conduction characteristics are low. . Furthermore, in Comparative Example 5, it is difficult to determine the quality because the particle size of the quality determination particles (particles D) is too small.
[0035]
In Comparative Example 6, the insulating property is low because the particle size of the pass / fail judgment particles (particle I) is too large. Furthermore, in Comparative Example 7, the particle size of the conductive particles (particle E) is too large to inhibit insulation, and the insulation characteristics are low. Furthermore, in Comparative Example 8, since the particle size distribution of the conductive particles (particles K) is too wide, the insulation is hindered and the insulating properties are low.
[0036]
Moreover, in the comparative example 9, there are many compounding quantities of the particle | grains for conduction | electrical_connection (particle | grains B), the insulation is inhibited and the insulation characteristic is low. Furthermore, in Comparative Example 10, the blending amount of the pass / fail judgment particles (particles C) is small, and it is difficult to check the pass / fail judgment particles, and pass / fail judgment is difficult. Furthermore, in Comparative Example 11, the blending amount of the pass / fail judgment particles (particles C) is large, which inhibits insulation and lowers the insulation characteristics.
[0037]
【The invention's effect】
As is clear from the above description, in the anisotropic conductive film of the present invention, conductive particles for conduction and particles for quality determination for quality determination of the connection state are dispersed in the insulating adhesive. And the compressive strength at the time of 10% displacement of the particles for pass / fail determination is smaller than the 10% compressive strength of the particles for conduction, and the average particle diameter of the particles for conduction is 3 to 10 μm. Since the particle diameter exceeds 5 μm and is 1.25 to 4 times the average particle diameter of the conductive particles, the conductive particles are blended in an amount of 10 to 20 parts by weight with respect to 1 part by weight of the pass / fail judgment particles. When connecting between electrodes using this, the pass / fail judgment particles are crushed earlier than the conduction particles, making it easier to check the pass / fail judgment particles, and the pass / fail judgment is easily performed. In addition, the pass / fail judgment particles may interfere with the connection between the electrodes. Absent.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating an example of a liquid crystal display device.
[Explanation of symbols]
5 Anisotropic conductive film, 6 Insulating adhesive, 7 Conductive particles

Claims

Conductive particles for conduction and pass / fail judgment particles for connection pass / fail judgment are dispersed in the insulating adhesive, and the compressive strength at the time of 10% displacement of the pass / fail judgment particles is the above-mentioned conductivity. Less than 10% compressive strength of the common particles, the average particle size of the conductive particles is 3 to 10 μm, the average particle size of the pass / fail judgment particles exceeds 5 μm , and the average particle size of the conductive particles is An anisotropic conductive film characterized in that it is 1.25 to 4 times, and 10 to 20 parts by weight of the conductive particles are blended with respect to 1 part by weight of the quality determination particles.

2. The anisotropic conductive film according to claim 1, wherein the conduction particles and the quality determination particles are particles obtained by gold-plating divinylbenzene coated with nickel.