JP3687044B2 - Copolymerized polyimide film and method for producing the same - Google Patents

Description

（Ｘは、水素、ハロゲン基、カルボキシル基、低級アルキル基、低級アルコキシ基から選ばれる１価の置換基を表わす。）
（Ｉ）式で表される剛構造の芳香族ジアミン化合物のうちでは、得られる成形体の弾性率を高める点では、Ｘが水素である８ものを使用するのが好ましく、その中でも特にパラフェニレンジアミンを使用するのがより好ましい。
【０００９】
柔構造の芳香族ジアミン化合物の例としては、下記（ＩＩ）式で表されるような化合物を挙げることができる。
【００１０】
【化５】

（Ｘ，Ｙは水素、ハロゲン基、カルボキシル基、低級アルキル基、低級アルコキシ基から選ばれる１価の置換基を表わし、Ｘ，Ｙは同じ置換基でも異なった置換基でもよい。また、Ａは−Ｏ−，−Ｓ−，−ＣＯ−，−ＳＯ−，−ＳＯ₂− ，−ＣＨ₂ −等の二価の連結基を表す。
【００１１】
（ＩＩ）式で表される柔構造の芳香族ジアミン化合物のうちでは、得られる成形体の成形性を高める点では、下記（ＩＩＩ）式で表されるようなアミノ基以外の置換基の無い芳香族ジアミン化合物が好ましい。
【００１２】
【化６】

（Ａは−Ｏ−，−Ｓ−，−ＣＯ−，−ＳＯ−，−ＳＯ₂−，−ＣＨ₂−から選ばれる２価の連結基を表わす。）
その中でも特に４，４’−ジアミノジフェニルエーテルを使用するのがより好ましい。
【００１３】
使用する芳香族ジアミン化合物の割合としては、全芳香族ジアミン成分に対して剛構造の芳香族ジアミン化合物を１２モル％以上３０モル％以下、柔構造の芳香族ジアミン化合物を７０モル％以上８８モル％以下使用する。剛構造の芳香族ジアミン化合物の使用割合が前記の割合より少なくなり、柔構造の芳香族ジアミン化合物の使用割合が多くなりすぎると、得られる共重合ポリイミド成形体の弾性率が低下したり、熱膨張係数が増大するので好ましくなく、また剛構造の芳香族ジアミン化合物の使用割合が前記の割合より多くなり、柔構造の芳香族ジアミン化合物の使用割合が少なくなると、共重合ポリイミド成形体の吸水率が増大したり、熱膨張係数が低下しすぎたり、弾性率が高くなりすぎて成形性を損なうので好ましくない。
【００１４】
使用する芳香族テトラカルボン酸類化合物としてはピロメリット酸類、３，３’，４，４’−ビフェニルテトラカルボン酸類および３，３’−４，４’−ベンゾフェノンテトラカルボン酸類から１種以上を選ぶのが好ましい。
【００１５】
使用する芳香族テトラカルボン酸類化合物で、ピロメリット酸類としてはピロメリット酸またはその二無水物を、３，３’−４，４’−ビフェニルテトラカルボン酸類としては３，３’−４，４’−ビフェニルテトラカルボン酸またはその二無水物を、３，３’−４，４’−ベンゾフェノンテトラカルボン酸類としては３，３’−４，４’−ベンゾフェノンテトラカルボン酸またはその二無水物をそれぞれ挙げることができる。
【００１６】
使用する芳香族テトラカルボン酸類化合物の割合としては、全芳香族テトラカルボン酸類成分に対してピロメリット酸類を５０モル％以上８０モル％以下、３，３’−４，４’−ビフェニルテトラカルボン酸類および／または、３，３’−４，４’−ベンゾフェノンテトラカルボン酸類を２０モル％以上５０モル％以下使用する。３，３’−４，４’−ビフェニルテトラカルボン酸類および／または、３，３’−４，４’−ベンゾフェノンテトラカルボン酸類の使用割合が前記の割合より少なくなると、得られる共重合ポリイミド成形体の弾性率が低下したり、吸水率が増大するので好ましくなく、また３，３’−４，４’−ビフェニルテトラカルボン酸類および／または、３，３’−４，４’−ベンゾフェノンテトラカルボン酸類の使用割合が前記の割合より多くなると、得られる共重合ポリイミドの気体透過率が悪化し、成形体の表面に気泡が発生したり、成形体の接着力が低下するので好ましくない。尚３，３’−４，４’−ビフェニルテトラカルボン酸類、３，３’−４，４’−ベンゾフェノンテトラカルボン酸類はそれぞれ単独で使用してもよいが、混合して使用してもよい。
【００１７】
次に、本発明の共重合ポリイミドの製造方法について説明する。まずポリイミドのブロック成分を形成させるために重合の第１段階で１種の剛構造の芳香族ジアミン化合物に対して１種の芳香族テトラカルボン酸類が９０モル％以上、１００モル％未満となる比率で、反応成分に対して非反応性の有機溶媒中で、１時間以上混合する。
【００１８】
続いて共重合ポリイミドのランダム成分を形成させるため重合の第２段階として柔構造の芳香族ジアミン化合物を添加した後、芳香族テトラカルボン酸類（Ａ）を添加して１時間以上撹拌、さらに芳香族テトラカルボン酸類（Ｂ；Ａ≠Ｂ）を全芳香族テトラカルボン酸類成分と全芳香族ジアミン成分とがほぼ等モルとなる量添加して、１時間以上撹拌する。一連の重合によりまず前駆体である共重合ポリアミド酸溶液が得られる。この共重合ポリアミド酸溶液を環化脱溶媒することによって共重合ポリイミドが得られる。この重合での第１段階と第２段階はアミン成分過剰下で連続して行われるため、それぞれで形成されるブロック重合ポリアミド酸成分とランダム共重合ポリアミド酸成分とが分子結合してなる共重合ポリアミド酸溶液を得、このポリアミド酸溶液を環化脱溶媒することにより、所望の共重合ポリイミドを得ることができる。
【００１９】
該製造方法における第１段階の重合では芳香族テトラカルボン酸類としてピロメリット酸類、３，３’−４，４’−ビフェニルテトラカルボン酸類、３，３’−４，４’−ベンゾフェノンテトラカルボン酸類いずれでも単独で使用してよいが、ピロメリット酸類を使用すると、最終的に得られる共重合ポリイミド成形体の弾性率を高めるので好ましい。また芳香族ジアミン成分としては剛構造の芳香族ジアミン化合物を使用する。
【００２０】
第２段階の重合では、芳香族テトラカルボン酸類として、ピロメリット酸類、３，３’−４，４’−ビフェニルテトラカルボン酸類および３，３’−４，４’−ベンゾフェノンテトラカルボン酸類から選ばれる１種以上の化合物を使用するのが好ましく、最終的に得られる共重合ポリイミド成形体の弾性率を高めるためにはピロメリット酸類と３，３’−４，４’−ビフェニルテトラカルボン酸類の組み合わせで使用するのが好ましい。また芳香族ジアミン成分としては柔構造の芳香族ジアミン化合物を使用する。
【００２１】
該製造方法で使用する溶媒としては、ジメチルスルホキシド、Ｎ，Ｎ−ジメチルアセトアミド、Ｎ，Ｎ−ジエチルアセトアミド、Ｎ，Ｎ−ジメチルホルムアミド、Ｎ，Ｎ−ジエチルホルムアミド、Ｎ−メチル−２−ピロリドンおよびジメチルスルホン等が挙げられ、これらを単独あるいは混合して使用するのが好ましい。該製造方法で得られる共重合ポリアミド酸は前記溶媒中に１０〜３０重量％の割合で調製する。
【００２２】
該製造方法で得られる共重合ポリアミド酸を環化させて共重合ポリイミドにする際、脱水剤と触媒を用いて脱水する化学閉環法、熱的に脱水する熱閉環法のいずれで行ってもよいが、化学閉環法で行った方が得られる共重合ポリイミド成形体の弾性率が高く、熱膨張係数が低くなり、さらにＴＡＢ用途で必要なケミカルエッチング性が付与できるので好ましい。化学閉環法で使用する脱水剤としては、無水酢酸等の脂肪族酸無水物、フタル酸無水物等の芳香族酸無水物等が挙げられ、これらを単独あるいは混合して使用する。また触媒としては、ピリジン、ピコリン、キノリン等の複素環式第３級アミン類、トリエチルアミン等の脂肪族第３級アミン類、Ｎ，Ｎ−ジメチルアニリン等の芳香族第３級アミン類等が挙げられ、これらを単独あるいは混合して使用する。
【００２３】
【実施例】
以下実施例により本発明を具体例に説明する。実施例中ＰＰＤはパラフェニレンジアミン、ＯＤＡは４，４’−ジアミノジフェニルエーテル、ＰＭＤＡはピロメリット酸二無水物、ＢＰＤＡは３，３’−４，４’−ジフェニルテトラカルボン酸二無水物、ＢＴＤＡは、３，３’−４，４’−ベンゾフェノンテトラカルボン酸二無水物、ＤＭＡｃはＮ，Ｎ−ジメチルアセトアミドを表す。
【００２４】
実施例１
５００ｍｌのセパラブルフラスコにＤＭＡｃ２３９．１ｇを入れ、ここにＰＰＤ１．８７０ｇ（０．０１７３モル）とＰＭＤＡ３．６５９ｇ（０．０１６８モル）を投入し、常温常圧中で１時間反応させた。次にここにＯＤＡ２５．３９８ｇ（０．１２６８モル）を投入し均一になるまで撹拌した後、ＢＰＤＡ８．４８１ｇ（０．０２８８モル）を添加し、１時間反応させた。続いてここにＰＭＤＡ２１．４９１ｇ（０．０９８５モル）を添加してさらに１時間反応させポリアミド酸溶液を得た。尚この重合で各原料の添加モル比は、表−１に示す割合で行い、固形分合計重量は、６０．９ｇに調製した。このポリアミド酸溶液から１５ｇを取り、厚み１２５μｍのポリエステルフィルム上に乗せた後、ミカサ製１Ｈ−３６０Ｓスピンコーターで２５００ｒｐｍの回転速度で１分間回転させた。続いてこれを無水酢酸、β−ピコリンの混合溶液に１０分間浸してイミド化反応させた後、ポリイミドゲルフィルムをポリエステルフィルムから剥がし、そのゲルフィルムを支持枠に固定した。その後３００℃で２０分間、続いて４００℃で５分間加熱乾燥した後、上記支持枠より取り外し、厚さ約２５μｍのポリイミドフィルムを得た。このフィルムの各特性の評価を行い、表−１にその結果を示した。
【００２５】
尚、各特性は次の方法で評価した。
【００２６】
（評価方法）
▲１▼弾性率
機器：ＲＴＭ−２５０
引張速度：１００ｍｍ／ｍｉｎ
荷重：１０ｋｇ
▲２▼熱膨張係数
機器：ＴＭＡ−５０
測定温度範囲：５０〜２００℃
昇温速度：１０℃／ｍｉｎ
▲３▼吸水率
９８％ＲＨ雰囲気下のデシケーター内に２日間静置し、元の重量に対しての 増加重量％で評価した。
【００２７】
実施例２〜１０
実施例１と同様の手順で、芳香族ジアミン成分および芳香族テトラカルボン酸成分を表１に示す割合でそれぞれポリアミド酸溶液を得た後、実施例１と同じ操作で得られたポリイミドフィルムの各特性評価を行い、表１にその結果を示した。
【００２８】
実施例１１
ＢＰＤＡをＢＴＤＡに置きかえ、原料の添加量を表１に示す割合で行った他は、実施例１と同様に操作を行いポリアミド酸溶液を得た後、実施例１と同じ操作で得られたポリイミドフィルムの各物性評価を行い、表１にその結果を示した。
【００２９】
実施例１２
５００ｍｌのセパラブルフラスコにＤＭＡｃ２３９．１ｇを入れ、ここにＰＰＤとＢＰＤＡを投入し、常温常圧中で１時間反応させた。次にここにＯＤＡを投入し均一になるまで撹拌した後、ＢＰＤＡを添加し、１時間反応させた。続いてここにＰＭＤＡを添加してさらに１時間反応させポリアミド酸溶液を得た。尚この重合で各原料の添加量は、表１に示す割合で行い、固形分合計重量は、６０．９ｇに調製した。この後ポリアミド酸溶液からポリイミドフィルムを得る操作については、実施例１と同様にして行い、ポリイミドフィルムの各物性評価結果を表１に示した。
【００３０】
比較例１
５００ｍｌのセパラブルフラスコにＤＭＡｃ２３９．１ｇを入れ、ここにＯＤＡとＰＭＤＡを投入し、常温常圧中で１時間反応させポリアミド酸溶液を得た。尚ＯＤＡとＰＭＤＡのモル比は、ほぼ１：１とし、固形分合計重量は、６０．９ｇに調製した。この後ポリアミド酸溶液からポリイミドフィルムを得る操作については、実施例１と同様にして行い、それぞれのポリイミドフィルムの各物性評価結果を表２に示した。
【００３１】
比較例２
５００ｍｌのセパラブルフラスコにＤＭＡｃ２３９．１ｇを入れ、ここにＰＰＤとＰＭＤＡを投入し、常温常圧中で１時間反応させた。次にここにＯＤＡを投入し均一になるまで撹拌した後、ＰＭＤＡを添加して１時間反応させポリアミド酸溶液を得た。尚この重合で各原料の添加量は、表２に示す割合で行い、固形分合計重量は、６０．９ｇに調製した。この後ポリアミド酸溶液からポリイミドフィルムを得る操作については、実施例１と同様にして行い、それぞれのポリイミドフィルムの各物性評価結果を表２に示した。
【００３２】
比較例３
５００ｍｌのセパラブルフラスコにＤＭＡｃ２３９．１ｇを入れ、ここにＰＰＤ、ＯＤＡ、ＢＰＤＡ、ＰＭＤＡを順次添加して常温常圧で２時間反応させポリアミド酸溶液を得た。尚この重合で各原料の添加量は、表２に示す割合で行い、固形分合計重量は、６０．９ｇに調製した。この後ポリアミド酸溶液からポリイミドフィルムを得る操作については、実施例１と同様にして行い、それぞれのポリイミドフィルムの各物性評価結果を表２に示した。
【００３３】
【表１】

【表２】

【００３４】
【発明の効果】
本発明で得られる共重合ポリイミドは２段階の重合を経ることにより剛構造の芳香族ジアミン化合物と芳香族テトラカルボン酸類化合物とからなるブロック重合ポリイミド成分と、柔構造の芳香族ジアミン化合物と少なくとも２種類以上の芳香族テトラカルボン酸類化合物とからなるランダム共重合ポリイミド成分とが、分子結合によって構成されるため、そのフィルムは、高い弾性率、低い熱膨張性、低い吸水性を併せ持つことができるので高加工性および高精度化の求められるＴＡＢのベースフィルムとして充分機能を果たすことができる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a copolymerized polyimide film having high elasticity, low thermal expansion comparable to metals, and low water absorption, and a method for producing the same.
[0002]
[Prior art]
Polyimide obtained by polycondensation of pyromellitic anhydride and 4,4'-diaminodiphenyl ether is used for electrical parts used in high-temperature environments because of its excellent heat resistance and electrical insulation. This polyimide film is used for applications such as flexible printed boards, taking advantage of its dimensional stability. More recently, it has been used as a base film for TAB (Tape Automated Bonding) tapes for mounting ICs and LSIs, and requires high workability and high precision. Low thermal expansion and low water absorption are required, and various studies have been conducted. For example, in Japanese Patent Laid-Open Nos. 60-210629, 64-16832, 64-16883, 64-16834, 1-13-11241, and 1-113142, the elastic modulus is increased. Describes examples of three-component polyimides using pyromellitic anhydride, 4,4′-diaminodiphenyl ether, and paraphenylenediamine in combination with paraphenylenediamine as a diamine component. In order to further increase the elastic modulus, development into a four-component polyimide in which 3,3′-4,4′-biphenyltetracarboxylic dianhydride is added to the above three-component system has also been performed. For example, JP-A 59-164328 and JP-A 61-111359 describe examples of quaternary polyimides. Another attempt to improve physical properties by controlling the monomer addition procedure during polymerization using a 4-component polyimide is disclosed in, for example, Japanese Patent Application Laid-Open No. 5-25273.
[0003]
[Problems to be solved by the invention]
As described above, in order to be used for TAB applications, its properties require high elastic modulus, low thermal expansion comparable to metals, and low water absorption. However, the three-component polyimides obtained in JP-A-60-210629, JP-A-64-16832, JP-A-64-16833, JP-A-64-16834, JP-A-1-131241, and JP-A-1-131242. Is higher in elastic modulus than polyimide obtained from pyromellitic anhydride and 4,4′-diaminodiphenyl ether, but still does not provide sufficient elastic modulus for TAB applications. In addition, in the four-component polyimides obtained in JP-A Nos. 59-164328 and 61-111359, it is necessary to increase the amount of paraphenylenediamine used in order to obtain a sufficient elastic modulus for TAB applications. As a result, there is a problem that the coefficient of thermal expansion is too lower than that of metal. In addition, the 4-component polyimide obtained in Japanese Patent Application Laid-Open No. 5-25273 has sufficient elasticity and thermal expansibility, but has a problem of high water absorption.
[0004]
Accordingly, it is an object of the present invention to provide a copolymerized polyimide film having high elasticity, low thermal expansion comparable to metals, and low water absorption, and a method for producing the same.
[0005]
[Means for Solving the Problems]
The present invention for solving the above-mentioned problems is represented by a polyimide block component comprising a rigid structure aromatic diamine compound represented by the formula (I) described later and an aromatic tetracarboxylic acid compound, and a formula (II) described later. that the aromatic diamine compound of the flexible structure and the random component of the copolymerized polyimide comprising at least two aromatic tetracarboxylic acid compound has a molecular bond and the total aromatic diamine, aromatic rigid structure A copolymerized polyimide film formed by forming a copolymerized polyimide having a diamine compound of 12 mol% to 30 mol% and a flexible aromatic diamine compound of 70 mol% to 88 mol%, or ( 1) Rigid aromatic diamine compound and aromatic tetracarboxylic acid compound in a non-reactive organic solvent with respect to the reaction components After mixing the aromatic tetracarboxylic acid compound at a ratio of 90 mol% or more and less than 100 mol% with respect to the amine compound for the time necessary for the reaction, (2) adding an aromatic diamine compound having a flexible structure, Add the aromatic tetracarboxylic acid compound (A) and add the aromatic tetracarboxylic acid compound (B; A ≠ B) in such an amount that the total aromatic tetracarboxylic acid component and the total aromatic diamine component are approximately equimolar. Then, it is mixed for a time required for the reaction, (3) the resulting copolymerized polyamic acid solution is formed into a film, and (4) cyclized desolventization to produce a copolymerized polyimide film .
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The block component of the polyimide constituting the copolymerized polyimide of the present invention is a repeating polyimide molecular chain obtained from one kind of rigid structure aromatic diamine compound and one kind of aromatic tetracarboxylic acid compound. It is obtained by forming in one step. The random component of the copolymerized polyimide is formed by reacting a flexible structure aromatic diamine compound and at least two kinds of aromatic tetracarboxylic acid compounds in the second stage of polymerization. The copolymerized polyimide comprising the polyimide block component and the random component of the copolymerized polyimide thus obtained by molecular bonding can have excellent physical properties such as high elasticity, low thermal expansion comparable to metals, and low water absorption.
[0007]
Examples of the rigid structure aromatic diamine compound used in the present invention include compounds represented by the following formula (I).
[0008]
[Formula 4]

(X represents a monovalent substituent selected from hydrogen, a halogen group, a carboxyl group, a lower alkyl group, and a lower alkoxy group.)
Of the aromatic diamine compounds having a rigid structure represented by the formula (I), it is preferable to use 8 compounds in which X is hydrogen in terms of increasing the elastic modulus of the resulting molded product, and paraphenylene is particularly preferred. More preferably, a diamine is used.
[0009]
Examples of the flexible structure aromatic diamine compound include compounds represented by the following formula (II).
[0010]
[Chemical formula 5]

(X and Y represent a monovalent substituent selected from hydrogen, a halogen group, a carboxyl group, a lower alkyl group, and a lower alkoxy group, and X and Y may be the same or different substituents. It represents a divalent linking group such as —O—, —S—, —CO—, —SO—, —SO ₂ —, —CH ₂ — and the like.
[0011]
Of the aromatic diamine compounds having a flexible structure represented by the formula (II), there is no substituent other than the amino group as represented by the following formula (III) in terms of improving the moldability of the obtained molded product. Aromatic diamine compounds are preferred.
[0012]
[Chemical 6]

(A represents a divalent linking group selected from —O—, —S—, —CO—, —SO—, —SO ₂ —, —CH ₂ —).
Among these, it is more preferable to use 4,4′-diaminodiphenyl ether.
[0013]
The ratio of the aromatic diamine compound used is 12 mol% to 30 mol% of the rigid aromatic diamine compound and 70 mol% to 88 mol of the flexible aromatic diamine compound with respect to the total aromatic diamine component. % Or less. If the use ratio of the rigid structure aromatic diamine compound is less than the above ratio and the use ratio of the soft structure aromatic diamine compound is too large, the elastic modulus of the resulting copolymerized polyimide molded article may be reduced, Since the expansion coefficient increases, it is not preferable, and when the use ratio of the aromatic diamine compound having a rigid structure is higher than the above ratio and the use ratio of the aromatic diamine compound having a soft structure is reduced, the water absorption rate of the copolymer polyimide molded body is reduced. Increases, the coefficient of thermal expansion decreases too much, or the modulus of elasticity increases too much to impair the moldability.
[0014]
As the aromatic tetracarboxylic acid compound to be used, one or more selected from pyromellitic acid, 3,3 ′, 4,4′-biphenyltetracarboxylic acid and 3,3′-4,4′-benzophenonetetracarboxylic acid are selected. Is preferred.
[0015]
The aromatic tetracarboxylic acid compound used is pyromellitic acid or its dianhydride as pyromellitic acid, and 3,3'-4,4 'as 3,3'-4,4'-biphenyltetracarboxylic acid. -Biphenyltetracarboxylic acid or its dianhydride, and 3,3'-4,4'-benzophenonetetracarboxylic acid as 3,3'-4,4'-benzophenonetetracarboxylic acid or its dianhydride, respectively. be able to.
[0016]
As a ratio of the aromatic tetracarboxylic acid compound to be used, pyromellitic acid is 50 mol% or more and 80 mol% or less, 3,3′-4,4′-biphenyl tetracarboxylic acid, based on the total aromatic tetracarboxylic acid component. And / or 3,3′-4,4′-benzophenonetetracarboxylic acid is used in an amount of 20 mol% to 50 mol%. Copolymerized polyimide molded body obtained when 3,3′-4,4′-biphenyltetracarboxylic acids and / or 3,3′-4,4′-benzophenonetetracarboxylic acids are used in a proportion less than the above ratio. This is not preferable because the elastic modulus of the resin decreases and the water absorption increases, and 3,3′-4,4′-biphenyltetracarboxylic acids and / or 3,3′-4,4′-benzophenonetetracarboxylic acids If the ratio of use is greater than the above ratio, the gas permeability of the resulting copolymerized polyimide is deteriorated, bubbles are generated on the surface of the molded body, and the adhesive strength of the molded body is reduced, which is not preferable. Incidentally, 3,3′-4,4′-biphenyltetracarboxylic acids and 3,3′-4,4′-benzophenonetetracarboxylic acids may be used alone or in combination.
[0017]
Next, the manufacturing method of the copolymer polyimide of this invention is demonstrated. First, in order to form a block component of polyimide, a ratio in which one aromatic tetracarboxylic acid is 90 mol% or more and less than 100 mol% with respect to one type of rigid aromatic diamine compound in the first stage of polymerization. In an organic solvent that is non-reactive with the reaction components, the mixture is mixed for 1 hour or longer.
[0018]
Subsequently, in order to form a random component of the copolymerized polyimide, a flexible aromatic diamine compound is added as the second stage of polymerization, then the aromatic tetracarboxylic acid (A) is added and stirred for 1 hour or more, and further aromatic Tetracarboxylic acids (B; A ≠ B) are added in an amount such that the wholly aromatic tetracarboxylic acid component and the wholly aromatic diamine component are approximately equimolar, and stirred for 1 hour or longer. First, a copolymerized polyamic acid solution as a precursor is obtained by a series of polymerizations. A copolymerized polyimide is obtained by cyclizing and desolvating the copolymerized polyamic acid solution. Since the first stage and the second stage in this polymerization are carried out continuously in the presence of an excess of the amine component, the copolymer formed by molecularly bonding the block-polymerized polyamic acid component and the random-copolymerized polyamic acid component formed in each of them. A desired copolymerized polyimide can be obtained by obtaining a polyamic acid solution and cyclizing and removing the polyamic acid solution.
[0019]
In the first stage polymerization in the production method, any of pyromellitic acids, 3,3′-4,4′-biphenyltetracarboxylic acids, 3,3′-4,4′-benzophenonetetracarboxylic acids as aromatic tetracarboxylic acids However, although it may be used alone, it is preferable to use pyromellitic acids because the elastic modulus of the finally obtained copolymerized polyimide molded body is increased. A rigid aromatic diamine compound is used as the aromatic diamine component.
[0020]
In the second stage polymerization, the aromatic tetracarboxylic acids are selected from pyromellitic acids, 3,3′-4,4′-biphenyltetracarboxylic acids and 3,3′-4,4′-benzophenonetetracarboxylic acids. It is preferable to use one or more compounds, and in order to increase the elastic modulus of the finally obtained copolymer polyimide molded body, a combination of pyromellitic acids and 3,3′-4,4′-biphenyltetracarboxylic acids Is preferably used. A flexible aromatic diamine compound is used as the aromatic diamine component.
[0021]
Solvents used in the production method include dimethyl sulfoxide, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylformamide, N, N-diethylformamide, N-methyl-2-pyrrolidone and dimethyl Examples thereof include sulfones, and these are preferably used alone or in combination. The copolymerized polyamic acid obtained by the production method is prepared in a proportion of 10 to 30% by weight in the solvent.
[0022]
When the copolymerized polyamic acid obtained by the production method is cyclized to form a copolymerized polyimide, either a chemical ring closure method using a dehydrating agent and a catalyst or a thermal ring closure method in which thermal dehydration is performed may be used. However, it is preferable to use the chemical ring closure method because the copolymer polyimide molded body obtained has a high elastic modulus, a low thermal expansion coefficient, and chemical etching properties necessary for TAB applications. Examples of the dehydrating agent used in the chemical ring closure method include aliphatic acid anhydrides such as acetic anhydride and aromatic acid anhydrides such as phthalic anhydride, which are used alone or in combination. Examples of the catalyst include heterocyclic tertiary amines such as pyridine, picoline and quinoline, aliphatic tertiary amines such as triethylamine, and aromatic tertiary amines such as N, N-dimethylaniline. These are used alone or in combination.
[0023]
【Example】
The present invention will be described below by way of specific examples. In the examples, PPD is paraphenylenediamine, ODA is 4,4′-diaminodiphenyl ether, PMDA is pyromellitic dianhydride, BPDA is 3,3′-4,4′-diphenyltetracarboxylic dianhydride, BTDA is 3,3′-4,4′-benzophenonetetracarboxylic dianhydride, DMAc represents N, N-dimethylacetamide.
[0024]
Example 1
DMAc 239.1g was put into a 500 ml separable flask, PPD1.870g (0.0173mol) and PMDA3.659g (0.0168mol) were thrown in here, and it was made to react at normal temperature normal pressure for 1 hour. Next, ODA25.398g (0.1268mol) was thrown here and it stirred until it became uniform, Then, BPDA8.481g (0.0288mol) was added, and it was made to react for 1 hour. Subsequently, 21.491 g (0.0985 mol) of PMDA was added thereto, and the mixture was further reacted for 1 hour to obtain a polyamic acid solution. In this polymerization, the addition molar ratio of each raw material was carried out in the ratio shown in Table 1, and the total solid content weight was adjusted to 60.9 g. 15 g of this polyamic acid solution was taken and placed on a 125 μm-thick polyester film, and then rotated for 1 minute at a rotation speed of 2500 rpm with a 1H-360S spin coater manufactured by Mikasa. Subsequently, this was immersed in a mixed solution of acetic anhydride and β-picoline for 10 minutes to cause an imidization reaction, and then the polyimide gel film was peeled off from the polyester film, and the gel film was fixed to a support frame. Thereafter, it was dried by heating at 300 ° C. for 20 minutes and then at 400 ° C. for 5 minutes, and then removed from the support frame to obtain a polyimide film having a thickness of about 25 μm. Each characteristic of this film was evaluated, and the results are shown in Table-1.
[0025]
Each characteristic was evaluated by the following method.
[0026]
(Evaluation methods)
(1) Elastic modulus equipment: RTM-250
Tensile speed: 100 mm / min
Load: 10kg
(2) Coefficient of thermal expansion: TMA-50
Measurement temperature range: 50-200 ° C
Temperature increase rate: 10 ° C / min
(3) Water absorption rate: 98% The sample was allowed to stand in a desiccator under an RH atmosphere for 2 days, and evaluated by an increase in weight% relative to the original weight.
[0027]
Examples 2-10
Each of the polyimide films obtained by the same procedure as in Example 1 was obtained in the same procedure as in Example 1 after obtaining the polyamic acid solution in the proportions shown in Table 1 for the aromatic diamine component and aromatic tetracarboxylic acid component. The characteristics were evaluated and the results are shown in Table 1.
[0028]
Example 11
A polyimide obtained by the same operation as in Example 1, after replacing BPDA with BTDA and performing the same procedure as in Example 1 to obtain a polyamic acid solution, except that the addition amount of raw materials was changed as shown in Table 1. The physical properties of the film were evaluated, and the results are shown in Table 1.
[0029]
Example 12
DMAc 239.1g was put into a 500 ml separable flask, PPD and BPDA were put here, and it was made to react at normal temperature normal pressure for 1 hour. Next, ODA was added here and stirred until uniform, then BPDA was added and allowed to react for 1 hour. Subsequently, PMDA was added thereto and reacted for another hour to obtain a polyamic acid solution. In addition, the addition amount of each raw material was performed by this polymerization in the ratio shown in Table 1, and the total solid content weight was adjusted to 60.9 g. Thereafter, an operation for obtaining a polyimide film from the polyamic acid solution was carried out in the same manner as in Example 1. Table 1 shows the results of evaluation of physical properties of the polyimide film.
[0030]
Comparative Example 1
DMAc 239.1g was put into a 500 ml separable flask, ODA and PMDA were put here, and it was made to react at normal temperature normal pressure for 1 hour, and the polyamic-acid solution was obtained. The molar ratio of ODA to PMDA was approximately 1: 1, and the total solid content weight was adjusted to 60.9 g. Thereafter, an operation for obtaining a polyimide film from the polyamic acid solution was carried out in the same manner as in Example 1. Table 2 shows the evaluation results of the properties of each polyimide film.
[0031]
Comparative Example 2
DMAc 239.1g was put into a 500 ml separable flask, PPD and PMDA were added here, and it was made to react at normal temperature normal pressure for 1 hour. Next, ODA was added thereto and stirred until uniform, then PMDA was added and reacted for 1 hour to obtain a polyamic acid solution. In this polymerization, the amount of each raw material was added in the ratio shown in Table 2, and the total solid content weight was adjusted to 60.9 g. Thereafter, an operation for obtaining a polyimide film from the polyamic acid solution was carried out in the same manner as in Example 1. Table 2 shows the evaluation results of the properties of each polyimide film.
[0032]
Comparative Example 3
239.1 g of DMAc was put into a 500 ml separable flask, and PPD, ODA, BPDA and PMDA were sequentially added thereto and reacted at room temperature and normal pressure for 2 hours to obtain a polyamic acid solution. In this polymerization, the amount of each raw material was added in the ratio shown in Table 2, and the total solid content weight was adjusted to 60.9 g. Thereafter, an operation for obtaining a polyimide film from the polyamic acid solution was carried out in the same manner as in Example 1. Table 2 shows the evaluation results of the properties of each polyimide film.
[0033]
[Table 1]

[Table 2]

[0034]
【The invention's effect】
The copolymerized polyimide obtained by the present invention undergoes a two-stage polymerization, whereby a block-polymerized polyimide component comprising a rigid structure aromatic diamine compound and an aromatic tetracarboxylic acid compound, a soft structure aromatic diamine compound and at least 2 Since the random copolymer polyimide component composed of more than one kind of aromatic tetracarboxylic acid compound is composed of molecular bonds, the film can have both high elastic modulus, low thermal expansion, and low water absorption. It can sufficiently function as a TAB base film that requires high workability and high precision.

Claims (9)

(I) below and an aromatic diamine compound represented by the rigid structure and an aromatic tetracarboxylic acid compound and a polyimide block component made of the formula, (II) below aromatic diamine compound of the flexible structure of the formula with at least 2 A random component of a copolymerized polyimide composed of a kind of aromatic tetracarboxylic acid compound is molecularly bonded , and a rigid aromatic diamine compound is 12 mol% or more and 30 mol% relative to the total aromatic diamine. A copolymerized polyimide film formed by forming a copolymerized polyimide having a flexible structure aromatic diamine compound of 70 mol% or more and 88 mol% or less.

(X represents a monovalent substituent selected from hydrogen, a halogen group, a carboxyl group, a lower alkyl group, and a lower alkoxy group.)

(X and Y represent a monovalent substituent selected from hydrogen, a halogen group, a carboxyl group, a lower alkyl group, and a lower alkoxy group, and A represents —O—, —S—, —CO—, —SO—, Represents a divalent linking group selected from —SO ₂ — and —CH ₂ —.) The copolymer polyimide film according to claim 1, wherein X in the formula (I) is hydrogen. The copolymer polyimide film according to claim 1 or 2, wherein the aromatic diamine compound having a rigid structure is a paraphenylenediamine. The copolymer polyimide film according to any one of claims 1 to 3, wherein the aromatic diamine compound having a flexible structure is a diamine represented by the following formula (III).

(A represents a divalent linking group selected from —O—, —S—, —CO—, —SO—, —SO ₂ —, —CH ₂ —). The copolymer polyimide film according to any one of claims 1 to 4, wherein the aromatic diamine compound having a flexible structure is 4,4'-diaminodiphenyl ether. The aromatic tetracarboxylic acid compound is one or more compounds selected from pyromellitic acids, 3,3 ′, 4,4′-biphenyltetracarboxylic acids and 3,3 ′ , 4,4′-benzophenone tetracarboxylic acids. copolymerization polyimide film 5 according to any one of claims 1. The pyromellitic acid is 50 mol% or more and 80 mol% or less of the total aromatic tetracarboxylic acid component, and 3,3 ′, 4,4′-biphenyltetracarboxylic acid and / or 3,3 ′ , 4,4 ′. The copolymer polyimide film according to any one of claims 1 to 6, wherein the benzophenone tetracarboxylic acid is 20 mol% to 50 mol% of the wholly aromatic tetracarboxylic acid component. (1) A rigid aromatic diamine compound and an aromatic tetracarboxylic acid compound in a non-reactive organic solvent with respect to a reaction component, and an aromatic tetracarboxylic acid compound with respect to a rigid aromatic diamine compound In a ratio of 90 mol% or more and less than 100 mol%, after mixing for the time required for the reaction,
(2) Add an aromatic diamine compound having a flexible structure, then add an aromatic tetracarboxylic acid compound (A), and further add an aromatic tetracarboxylic acid compound (B; A ≠ B) to a fully aromatic tetracarboxylic acid component And the total aromatic diamine component are added in an amount that is approximately equimolar, and mixed for the time required for the reaction,
(3) The resulting copolymerized polyamic acid solution is made into a film,
(4) A method for producing a copolymerized polyimide film , characterized by carrying out cyclization and desolvation. The method for producing a copolymerized polyimide film according to claim 8, wherein the cyclization is performed by a chemical cyclization method using a cyclization catalyst and a dehydrating agent.