TW202300565A - Resin composition, manufacturing method of cured product, and cured product - Google Patents

Abstract

The present invention provides a polyamic acid-containing resin composition excellent in film formation property and capable of stably forming a cured product containing polyimide, a method for producing a cured product using the resin composition, and a cured product formed by curing the resin composition. This invention is characterized in that the resin composition containing polyamic acid (A) is blended with one or more selected from the group consisting of a carbonyloxy compound (B1) having a -CO-O- bond in the molecule, and a basic nitrogen-containing compound (B2) having no -CO-O- bond in the molecule.

Description

Resin composition, method for producing cured product, and cured product

The present invention relates to a resin composition containing polyamic acid, a method for producing a cured product using the resin composition, and a cured product obtained by curing the resin composition.

Polyimide resin is widely used in electrical and electronic parts such as various components or electronic substrates such as multilayer wiring boards due to its excellent heat resistance, mechanical strength, insulation, and low dielectric constant. insulating or protective material. Generally, polyimide resins are formed by heat-treating polyamic acid, which is obtained by polymerizing tetracarboxylic dianhydride components and diamine components in a polar organic solvent. In this context, polyimide products for electronic materials are mostly supplied in the form of solutions of polyimide precursors such as polyamic acid. Specifically, when manufacturing electrical and electronic parts, the solution of the polyimide precursor is supplied to the position where the insulating material or protective material is to be formed by coating, injecting, etc., and the effect of the polyimide precursor is The solution is heat treated to form an insulating or protective material. Efforts have been made in the industry regarding technical development of such polyimide resins. For example, as an example of Patent Document 1, a method for producing a polyimide resin is disclosed in which 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane and 3,3 ',4,4'-Diphenyl ether tetracarboxylic dianhydride was reacted in propylene glycol monomethyl ether acetate and imidized at 150°C. [Prior Art Literature] [Patent Document] [Patent Document 1] Japanese Patent Laid-Open No. 2012-021133

(式(a1)中，A為碳原子數6～50之4價有機基，B為2價有機基) 本發明之第2態樣係一種硬化物之製造方法，其包括如下步驟： 塗膜形成步驟，於基材上塗佈第1態樣之樹脂組合物而形成塗膜；及 加熱步驟，於70～550℃下對上述塗膜進行加熱。 本發明之第3態樣係一種硬化物，其係使第1態樣之樹脂組合物硬化而成。 [發明之效果] 根據本發明，可提供製膜性優異、能夠穩定地形成含有聚醯亞胺之硬化物的含有聚醯胺酸之樹脂組合物、使用該樹脂組合物之硬化物之製造方法、及使該樹脂組合物硬化而成之硬化物。 [Problems to be Solved by the Invention] Here, the inventors of the present invention found out through studies that if the conditions are not properly set in the process of heating and hardening the polyimide resin precursor, it will harden. Behavior is unstable, and as a result, film production, etc. may not be performed smoothly. Such a polyimide film with an incomplete film-forming state is also poor in appearance, so the industry strongly expects the development of a composition capable of stably forming a film. The present invention was made in view of the above problems, and an object of the present invention is to provide a resin composition containing polyimide that is excellent in film-forming properties and can stably form a cured product containing polyimide, and a cured product using the resin composition. A method for producing a product, and a cured product obtained by curing the resin composition. [Technical Means for Solving the Problems] In order to solve the above-mentioned problems, the inventors of the present invention have made intensive studies. As a result, it has been found that the above-mentioned problems can be solved by blending a polyamide acid (A)-containing resin composition containing carbonyl oxides selected from the group consisting of -CO-O- bonds in the molecule, and completed the present invention. One or more of the group consisting of a base compound (B1) and a basic nitrogen-containing compound (B2) without a -CO-O- bond in the molecule. Specifically, the present invention provides the following. The first aspect of the present invention is a resin composition comprising a polyamic acid (A) having a structural unit represented by the following formula (a1), and a carbonyl oxide selected from a group having a -CO-O- bond in the molecule. One or more of the group consisting of a base compound (B1) and a basic nitrogen-containing compound (B2) without a -CO-O- bond in the molecule. [chemical 1]

(In the formula (a1), A is a tetravalent organic group with 6 to 50 carbon atoms, and B is a divalent organic group) The second aspect of the present invention is a method for producing a cured product, which includes the following steps: coating A forming step of coating the resin composition of the first aspect on the substrate to form a coating film; and a heating step of heating the above coating film at 70-550°C. A third aspect of the present invention is a cured product obtained by curing the resin composition of the first aspect. [Effects of the Invention] According to the present invention, it is possible to provide a polyamic acid-containing resin composition that is excellent in film-forming properties and can stably form a polyimide-containing cured product, and a method for producing a cured product using the resin composition. , and a cured product obtained by curing the resin composition.

(式(a1)中，A為碳原子數6～50之4價有機基，B為2價有機基) 此處，分子內具有-CO-O-鍵之羰基氧基化合物(B1)、及分子內不具有-CO-O-鍵之鹼性含氮化合物(B2)(以下，有時亦簡稱為「羰基氧基化合物(B1)」或「鹼性含氮化合物(B2)」)分別具有促進聚醯胺酸(A)向聚醯亞胺樹脂之轉化之效果。 因此，於對樹脂組合物進行加熱時，聚醯胺酸(A)之醯亞胺化均一且快速地進行，結果於硬化物之表面不易產生凹凸、翹曲、裂紋等，而能夠形成具有平滑表面、外觀優異之硬化物。 如上所述，上述之樹脂組合物以適當之速度進行硬化，而穩定地提供含有聚醯亞胺樹脂之硬化物。 以下，對樹脂組合物中所含之必須或任意之成分進行說明。 ＜聚醯胺酸(A)＞ 樹脂組合物含有聚醯胺酸(A)。聚醯胺酸(A)係於使樹脂組合物硬化時生成之聚醯亞胺之前驅物聚合物。 聚醯胺酸具有以下之式(a1)所表示之結構單元。 [化3]

(式(a1)中，A為碳原子數6～50之4價有機基，B為2價有機基) 上述之聚醯胺酸(A)通常藉由將四羧酸二酐與二胺化合物進行縮合而獲得。 以下，對製造聚醯胺酸(A)時所使用之四羧酸二酐、二胺化合物、及聚醯胺酸(A)之製造方法進行說明。 [四羧酸二酐] 生成式(a1)所表示之結構單元之四羧酸二酐以下式(a1-1)表示。 式(a1-1)所表示之四羧酸二酐與下述之二胺化合物進行反應，而生成具有式(a1)所表示之結構單元之聚醯胺酸(A)。該四羧酸二酐可單獨用1種，亦可將2種以上組合而使用。 [化4]

(式(a1-1)中，A為碳原子數6～50之4價有機基) 式(a1-1)中，A為碳原子數6～50之4價有機基，除了具有式(a1-1)中之2個-CO-O-CO-所表示之酸酐基以外，亦可具有一個或複數個取代基。 作為取代基之適宜例，較佳為氟原子、碳原子數1～6之烷基、碳原子數1～6之烷氧基、碳原子數1～6之氟化烷基、碳原子數1～6之氟化烷氧基，又，除了式(a1-1)所表示之酸酐基以外，亦可含有羧基、羧酸酯基。 於取代基為氟化烷基或氟化烷氧基之情形時，較佳為全氟烷基或全氟烷氧基。 關於以上之取代基，對於下述之芳香族基可於芳香環上具有之一個或複數個取代基而言亦相同。 式(a1-1)中，A為4價有機基，其碳原子數之下限值為6，上限值為50。 構成A之碳原子數更佳為8以上，進而較佳為12以上。又，構成A之碳原子數更佳為40以下，進而較佳為30以下。A可為脂肪族基，亦可為芳香族基，亦可為將該等結構組合而成之基。A除了含有碳原子及氫原子以外，亦可含有鹵素原子、氧原子、及硫原子。於A含有氧原子、氮原子、或硫原子之情形時，氧原子、氮原子、或硫原子可以選自含氮雜環基、-CONH-、-NH-、-N＝N-、-CH＝N-、-COO-、-O-、-CO-、-SO-、-SO ₂-、-S-、及-S-S-中之基之形式含有於A中，更佳為以選自-O-、-CO-、-SO-、-SO ₂-、-S-、及-S-S-中之基之形式含有於A中。 四羧酸二酐可從先前用作聚醯胺酸之合成原料的四羧酸二酐中適當選擇。四羧酸二酐可為脂肪族四羧酸二酐，亦可為芳香族四羧酸二酐。 作為脂肪族四羧酸二酐，例如可列舉2,2-雙(3,4-二羧基)丙烷二酐、雙(3,4-二羧基)甲烷二酐等，又，亦可為含有脂環式結構者。該脂環式結構亦可為多環式，作為多環式之脂環式結構，例如可列舉雙環[2.2.1]庚烷等具有橋接脂環式結構之結構等，例如橋接脂環式結構亦可與其他之橋接脂環式結構及/或非橋接脂環式結構進行縮合，橋接脂環式結構亦可藉由螺接而與其他之橋接脂環式結構及/或非橋接脂環式結構進行連結。於使用脂肪族四羧酸二酐之情形時，有使用樹脂組合物容易獲得透明性優異之硬化物之傾向。 又，作為構成式(a1-1)中之A之脂肪族基，例如可採用以下之式(a2)所表示之4價基。於使用此種基之情形時，有容易獲得具有透明性之聚醯亞胺膜之傾向。 再者，對於式(a2)中之n而言，就容易進行原料化合物之精製之觀點而言，n較佳為5以下，更佳為3以下。又，就可生成式(a1)所表示之結構體的原料化合物之化學穩定性優異之觀點而言，n較佳為1以上，更佳為2以上。 式(a2)中之n尤佳為2或3。 [化5]

(式(a2)中，R ^a11、R ^a12、及R ^a13各自獨立為選自由氫原子、碳原子數1～5之烷基及氟原子所組成之群中之1種，n為0～12之整數) 作為芳香族四羧酸二酐，例如可列舉：焦蜜石酸二酐、1,4-雙(3,4-二羧基苯氧基)苯二酐、3,3',4,4'-氧雙鄰苯二甲酸二酐、3,3',4,4'-聯苯四羧酸二酐、2,3,3',4'-聯苯四羧酸二酐、3,3',4,4'-二苯甲酮四羧酸二酐、3,3',4,4'-二苯碸四羧酸二酐等。 又，作為芳香族四羧酸二酐，例如亦可為下述通式(a1-2)～(a1-4)所表示者。 [化6]

上述式(a1-2)及(a1-3)中，R ^a1、R ^a2及R ^a3各自為可經鹵素取代之脂肪族基、氧原子、硫原子、經由1個以上之2價元素之芳香族基中之任一者，或表示由其等之組合構成之2價取代基。R ^a2及R ^a3可相同亦可不同。 即，R ^a1、R ^a2及R ^a3亦可含有碳-碳單鍵、碳-氧-碳醚鍵或鹵族元素(氟、氯、溴、碘)，可列舉：2,2-雙(3,4-二羧基三氟苯氧基)丙烷二酐、1,4-雙(3,4-二羧基三氟苯氧基)苯二酐、1,4-雙(3,4-二羧基三氟苯氧基)四氯苯二酐、2,2',5,5',6,6'-六氟-3,3',4,4',-聯苯四羧酸二酐等。 又，於上述式(a1-4)中，R ^a4、R ^a5為可經鹵素取代之脂肪族基、經由1個以上之2價元素之芳香族基、鹵素中之任一種，或表示由其等之組合構成之1價取代基，各自可相同亦可不同，亦可使用二氟焦蜜石酸二酐、二氯焦蜜石酸二酐等。 作為用於獲得於分子結構內含有氟之含氟聚醯亞胺之四羧酸二酐，例如可列舉：(三氟甲基)焦蜜石酸二酐、二(三氟甲基)焦蜜石酸二酐、二(七氟丙基)焦蜜石酸二酐、五氟乙基焦蜜石酸二酐、雙{3,5-二(三氟甲基)苯氧基}焦蜜石酸二酐、2,2-雙(3,4-二羧基苯基)六氟丙烷二酐、5,5'-雙(三氟甲基)-3,3',4,4'-四羧基聯苯二酐、2,2',5,5'-四(三氟甲基)-3,3',4,4'-四羧基聯苯二酐、5,5'-雙(三氟甲基)-3,3',4,4'-四羧基二苯基醚二酐、5,5'-雙(三氟甲基)-3,3',4,4'-四羧基二苯甲酮二酐、雙{(三氟甲基)二羧基苯氧基}苯二酐、雙{(三氟甲基)二羧基苯氧基}(三氟甲基)苯二酐、雙(二羧基苯氧基)(三氟甲基)苯二酐、雙(二羧基苯氧基)雙(三氟甲基)苯二酐、雙(二羧基苯氧基)四(三氟甲基)苯二酐、2,2-雙{4-(3,4-二羧基苯氧基)苯基}六氟丙烷二酐、雙{(三氟甲基)二羧基苯氧基}聯苯二酐、雙{(三氟甲基)二羧基苯氧基}雙(三氟甲基)聯苯二酐、雙{(三氟甲基)二羧基苯氧基}二苯基醚二酐、雙(二羧基苯氧基)雙(三氟甲基)聯苯二酐、二氟焦蜜石酸二酐、1,4-雙(3,4-二羧基三氟苯氧基)四氟苯二酐、1,4-雙(3,4-二羧基三氟苯氧基)八氟聯苯二酐等。 作為四羧酸二酐，於考慮到所獲得之膜或成型體之耐熱性、拉伸伸長率及耐化學藥品性等之情形時，較佳為使用芳香族四羧酸二酐，就價格、易取得性等方面而言，較佳為使用3,3',4,4'-聯苯四羧酸二酐、及焦蜜石酸二酐。 再者，亦可使用具有與該等相同之基本骨架的四羧酸之醯氯化物、酯化物等。 於本實施形態中，四羧酸二酐亦可與二羧酸酐併用。若併用上述羧酸酐，則有時所獲得之聚醯亞胺樹脂等含醯亞胺環之聚合物之特性變得進一步良好。作為二羧酸酐，例如可列舉：順丁烯二酸酐、琥珀酸酐、伊康酸酐、鄰苯二甲酸酐、四氫鄰苯二甲酸酐、六氫鄰苯二甲酸酐、甲基內亞甲基四氫鄰苯二甲酸酐、氯橋酸酐(chlorendic anhydride)、甲基四氫鄰苯二甲酸酐、戊二酸酐、順式-4-環己烯-1,2-二甲酸酐等。 [二胺化合物] 二胺化合物典型而言可使用下式(a3-1)所表示之化合物。二胺化合物可單獨用1種，亦可將2種以上組合而使用。 H ₂N-B-NH ₂……(a3-1) (式(a3-1)中，B表示2價有機基) 式(a3-1)中，B為2價有機基，除了式(a3-1)中之2個胺基以外，亦可具有一個或複數個取代基。 作為取代基之適宜例，較佳為氟原子、碳原子數1～6之烷基、碳原子數1～6之烷氧基、碳原子數1～6之氟化烷基、碳原子數1～6之氟化烷氧基、羥基。 於取代基為氟化烷基或氟化烷氧基之情形時，較佳為全氟烷基或全氟烷氧基。 式(a3-1)中，作為B之有機基之碳原子數之下限值較佳為2，更佳為6，作為上限值，較佳為50，更佳為30。 B雖然亦可為脂肪族基，但較佳為含有1個以上芳香環之有機基。 於B為含有1個以上芳香環之有機基之情形時，該有機基可為1個芳香族基本身，亦可為將2個以上之芳香族基經由脂肪族烴基及鹵代脂肪族烴基、含有氧原子、硫原子及氮原子等雜原子之鍵進行鍵結而成之基。作為B中所含之含有氧原子、硫原子及氮原子等雜原子之鍵，可列舉-CONH-、-NH-、-N＝N-、-CH＝N-、-COO-、-O-、-CO-、-SO-、-SO ₂-、-S-、及-S-S-等，較佳為-O-、-CO-、-SO-、-SO ₂-、-S-、及-S-S-。 B中之與胺基鍵結之芳香環較佳為苯環。於B中之與胺基鍵結之環為包含2個以上環之縮合環之情形時，該縮合環中之與胺基鍵結之環較佳為苯環。 又，B中包含之芳香環亦可為芳香族雜環。 於B為包含芳香族環之有機基之情形時，就使用樹脂組合物所形成之硬化物之耐熱性之方面而言，該有機基較佳為下式(1)～(4)所表示之基中之至少1種。 [化7]

(式(1)～(4)中，R ¹¹表示選自由氫原子、氟原子、羥基、碳原子數1～4之烷基、及碳原子數1～4之鹵代烷基所組成之群中之1種；式(4)中，Q表示9,9'-亞茀基(fluorenylidene)、或選自由式-C ₆H ₄-、-CONH-C ₆H ₄-NHCO-、-NHCO-C ₆H ₄-CONH-、-O-C ₆H ₄-CO-C ₆H ₄-O-、-OCO-C ₆H ₄-COO-、-OCO-C ₆H ₄-C ₆H ₄-COO-、-OCO-、-O-、-S-、-CO-、-CONH-、-SO ₂-、-C(CF ₃) ₂-、-C(CH ₃) ₂-、-CH ₂-、-O-C ₆H ₄-C(CH ₃) ₂-C ₆H ₄-O-、-O-C ₆H ₄-C(CF ₃) ₂-C ₆H ₄-O-、-O-C ₆H ₄-SO ₂-C ₆H ₄-O-、-C(CH ₃) ₂-C ₆H ₄-C(CH ₃) ₂-、-O-C ₁₀H ₆-O-、-O-C ₆H ₄-C ₆H ₄-O-、及-O-C ₆H ₄-O-表示之基所組成之群中之1種； Q之示例中，-C ₆H ₄-為伸苯基，較佳為間伸苯基、及對伸苯基，更佳為對伸苯基；又，-C ₁₀H ₆-為萘二基(naphthalenediyl)，較佳為1,2-萘二基、1,4-萘二基、2,3-萘二基、2,6-萘二基、及2,7-萘二基，更佳為1,4-萘二基、及2,6-萘二基。 作為式(1)～(4)中之R ¹¹，就所形成之硬化物之耐熱性之方面而言，更佳為氫原子、羥基、氟原子、甲基、乙基、或三氟甲基，尤佳為氫原子、羥基、或三氟甲基。 作為式(4)中之Q，就所形成之硬化物之耐熱性之方面而言，較佳為9,9'-亞茀基、-O-C ₆H ₄-O-、-C(CF ₃) ₂-、-O-、-C(CH ₃) ₂-、-CH ₂-、或-O-C ₆H ₄-C(CH ₃) ₂-C ₆H ₄-O-、-CONH-，尤佳為-O-C ₆H ₄-O-、-C(CF ₃) ₂-或-O-。 於使用芳香族二胺作為式(a3-1)所表示之二胺化合物之情形時，例如可適宜地使用以下所示之芳香族二胺。 即，作為芳香族二胺，可列舉：對苯二胺、間苯二胺、2,4-二胺基甲苯、4,4'-二胺基聯苯、4,4'-二胺基-2,2'-雙(三氟甲基)聯苯、3,3'-二胺基二苯碸、4,4'-二胺基二苯碸、4,4'-二胺基二苯硫醚、4,4'-二胺基二苯甲烷、4,4'-二胺基二苯基醚、3,4'-二胺基二苯基醚、3,3'-二胺基二苯基醚、1,4-雙(4-胺基苯氧基)苯、1,3-雙(4-胺基苯氧基)苯、1,3-雙(3-胺基苯氧基)苯、4,4'-雙(4-胺基苯氧基)聯苯、雙[4-(4-胺基苯氧基)苯基]碸、雙[4-(3-胺基苯氧基)苯基]碸、2,2-雙[4-(4-胺基苯氧基)苯基]丙烷、2,2-雙[4-(4-胺基苯氧基)苯基]六氟丙烷、9,9-雙(4-胺基苯基)茀、9,9-雙(4-胺基-3-甲基苯基)茀、及4,4'-[1,4-伸苯基雙(1-甲基乙烷-1,1-二基)]二苯胺等。該等中，就價格、易取得性等方面而言，較佳為對苯二胺、間苯二胺、2,4-二胺基甲苯、及4,4'-二胺基二苯基醚。 又，作為B，可採用含矽原子之基，該矽原子亦可具有鏈狀之脂肪族基及/或芳香族環。作為此種含矽原子之基，典型而言可使用以下所示之基。 [化8]

又，就進一步提高所獲得之硬化物之機械特性之觀點而言，作為B，亦可較佳地使用下式(Si-1)所表示之基。 [化9]

(式(Si-1)中，R ¹²及R ¹³各自獨立為單鍵或亞甲基、碳原子數2～20之伸烷基、碳原子數3～20之伸環烷基、或碳原子數6～20之伸芳基等，R ¹⁴、R ¹⁵、R ¹⁶、及R ¹⁷各自獨立為碳原子數1～20之烷基、碳原子數3～20之環烷基、碳原子數6～20之芳基、碳原子數為20以下之含有胺基之基、-O-R ¹⁸表示之基(R ¹⁸為碳原子數1～20之烴基)、碳原子數為2～20之含有1個以上環氧基之有機基，l為3～50之整數) 作為式(Si-1)中之R ¹²及R ¹³中之碳原子數2～20之伸烷基，就耐熱性、殘留應力之觀點而言，較佳為碳原子數2～10之伸烷基，可列舉二亞甲基、三亞甲基、四亞甲基、五亞甲基、六亞甲基等。 作為式(Si-1)中之R ¹²及R ¹³中之碳原子數3～20之伸環烷基，就耐熱性、殘留應力之觀點而言，較佳為碳原子數3～10之伸環烷基，可列舉：伸環丁基、伸環戊基、伸環己基、伸環庚基等。 作為式(Si-1)中之R ¹²及R ¹³中之碳原子數6～20之伸芳基，就耐熱性、殘留應力之觀點而言，較佳為碳原子數6～20之芳香族基，可列舉：伸苯基、伸萘基等。 作為式(Si-1)中R ¹⁴、R ¹⁵、R ¹⁶、及R ¹⁷中之碳原子數1～20之烷基，就耐熱性與殘留應力之觀點而言，較佳為碳原子數1～10之烷基，具體而言，可列舉：甲基、乙基、丙基、異丙基、丁基、異丁基、第三丁基、戊基、己基等。 作為式(Si-1)中R ¹³、R ¹⁵、R ¹⁶、及R ¹⁷中之碳原子數3～20之環烷基，就耐熱性、殘留應力之觀點而言，較佳為碳原子數3～10之環烷基，具體而言，可列舉：環戊基、環己基等。 作為式(Si-1)中R ¹⁴、R ¹⁵、R ¹⁶、及R ¹⁷中之碳原子數6～20之芳基，就耐熱性、殘留應力之觀點而言，較佳為碳原子數6～12之芳基，具體而言，可列舉苯基、甲苯基、萘基等。 作為式(Si-1)中R ¹⁴、R ¹⁵、R ¹⁶、及R ¹⁷中之碳原子數20以下之含有胺基之基，可列舉：胺基、經取代之胺基(例如，雙(三烷基矽烷基)胺基)等。 作為式(Si-1)中R ¹⁴、R ¹⁵、R ¹⁶、及R ¹⁷中之-O-R ¹⁸所表示之基，可列舉：甲氧基、乙氧基、丙氧基、異丙氧基、丁氧基、苯氧基、甲苯基氧基、萘氧基、丙烯氧基(例如，烯丙氧基)、及環己氧基等。 其中，作為R ¹⁴、R ¹⁵、R ¹⁶、及R ¹⁷，較佳為甲基、乙基、丙基、苯基。 式(Si-1)所表示之基可藉由使兩末端具有胺基之含矽化合物作用於酸酐而導入。作為此種含矽化合物之具體例，可列舉兩末端胺基改性甲基苯基聚矽氧(例如信越化學公司製造之X-22-1660B-3(數量平均分子量為4,400左右)及X-22-9409(數量平均分子量為1,300左右))、兩末端胺基改性二甲基聚矽氧(例如信越化學公司製造之X-22-161A(數量平均分子量為1,600左右)、X-22-161B(數量平均分子量為3,000左右)及KF8012(數量平均分子量為4,400左右)；Dow Corning Toray製造之BY16-835U(數量平均分子量為900左右)；以及JNC公司製造之Silaplane FM3311(數量平均分子量為1000左右))等。 [聚醯胺酸(A)之製造方法] 典型而言，具有式(a1)所表示之結構單元之聚醯胺酸(A)係使上述之式(a1-1)所表示之四羧酸二酐與上述之式(a3-1)所表示之二胺化合物於溶劑中進行反應而獲得之聚合物，亦可為使用二胺化合物及/或四羧酸二酐各1種或2種以上而獲得之聚合物。例如，可為將二胺化合物與含有2種以上之四羧酸二酐之混合物進行縮聚合而獲得之聚合物。又，聚醯胺酸(A)可單獨使用，或將2種以上混合而使用。 合成聚醯胺酸(A)時之四羧酸二酐及二胺化合物之使用量並無特別限定，相對於1莫耳四羧酸二酐，較佳為使用0.50～1.50莫耳之二胺化合物，更佳為使用0.60～1.30莫耳，尤佳為使用0.70～1.20莫耳。 又，所獲得之聚醯胺酸(A)之重量平均分子量根據其用途而適當設定即可，例如為5000以上，較佳為7500以上，更佳為10000以上。另一方面，所獲得之聚醯胺酸(A)之重量平均分子量為例如100000以下，較佳為80000以下，更佳為75000以下。 該重量平均分子量可藉由對四羧酸二酐與二胺化合物之調配量、溶劑、或反應溫度等反應條件進行調整而使其成為上述值。 四羧酸二酐與二胺化合物之反應通常於有機溶劑中進行。四羧酸二酐與二胺化合物之反應中使用之有機溶劑而言，只要為能夠使四羧酸二酐及二胺化合物溶解且不與四羧酸二酐及二胺化合物反應之有機溶劑即可，並無特別限定。有機溶劑可單獨使用，或將2種以上混合而使用。 作為四羧酸二酐與二胺化合物之反應中使用之有機溶劑之例子，可列舉：N-甲基-2-吡咯啶酮、N,N-二甲基乙醯胺、N,N-二乙基乙醯胺、N,N-二甲基甲醯胺、N,N-二乙基甲醯胺、N-甲基己內醯胺、及N,N,N',N'-四甲基脲等含氮極性溶劑；二甲基亞碸；乙腈；二乙二醇二甲基醚、二乙二醇二乙基醚、二㗁烷、及四氫呋喃等醚類。 該等有機溶劑中，就所生成之聚醯胺酸(A)、聚醯亞胺樹脂之溶解性之方面而言，較佳為N-甲基-2-吡咯啶酮、N,N-二甲基乙醯胺、N,N-二乙基乙醯胺、N,N-二甲基甲醯胺、N,N-二乙基甲醯胺、N-甲基己內醯胺、及N,N,N',N'-四甲基脲等含氮極性溶劑。 使四羧酸二酐與二胺化合物進行反應時之溫度只要反應能夠良好地進行，則無特別限定。典型而言，四羧酸二酐與二胺化合物之反應溫度較佳為-5～150℃，更佳為0～120℃，尤佳為0～70℃。使四羧酸二酐與二胺化合物進行反應之時間根據反應溫度而異，典型而言，較佳為1～50小時，更佳為2～40小時，尤佳為5～30小時。 藉由以上所說明之方法，可獲得含有聚醯胺酸(A)之溶液。製備第1態樣之該樹脂組合物的方法並無特別限定，較佳為向所獲得之含有聚醯胺酸(A)之溶液中調配選自由分子內具有-CO-O-鍵之羰基氧基化合物(B1)、及分子內不具有-CO-O-鍵之鹼性含氮化合物(B2)所組成之群中之1種以上的方法。 可將如上所述含有聚醯胺酸(A)之溶液直接用於樹脂組合物之製備，亦可將聚醯胺酸之糊劑或固體用於樹脂組合物之製備，該糊劑或固體係於減壓下、於不發生聚醯胺酸向聚醯亞胺樹脂之轉化之程度之低溫下從聚醯胺酸(A)之溶液中去除溶劑之至少一部分而獲得。 ＜羰基氧基化合物(B1)及鹼性含氮化合物(B2)＞ 樹脂組合物含有選自由分子內具有-CO-O-鍵之羰基氧基化合物(B1)、及分子內不具有-CO-O-鍵之鹼性含氮化合物(B2)所組成之群中之1種以上。羰基氧基化合物(B1)及鹼性含氮化合物(B2)分別為促進由聚醯胺酸(A)生成聚醯亞胺之成分。 因此，若使用第1態樣之樹脂組合物，則聚醯胺酸(A)以適當之速度轉化為聚醯亞胺，容易獲得形狀穩定之硬化物。 雖然僅使用羰基氧基化合物(B1)及鹼性含氮化合物(B2)中之任一者亦獲得促進聚醯亞胺之生成之效果，但就樹脂組合物之硬化性之觀點而言，較佳為將羰基氧基化合物(B1)與鹼性含氮化合物(B2)組合而調配至樹脂組合物中。 以下，分別對羰基氧基化合物(B1)及鹼性含氮化合物(B2)進行說明。 [羰基氧基化合物(B1)] 作為羰基氧基化合物，只要為分子內具有-CO-O-鍵之化合物即可，並無特別限定。羰基氧基化合物(B1)藉由促進聚醯胺酸(A)中之因脫水引起之閉環，而使樹脂組合物之硬化良好地進行。 作為羰基氧基化合物(B1)，例如可列舉：羧酸、羧酸酯、羧酸酐、碳酸酯等。 羰基氧基化合物(B1)亦可將2種以上組合而使用。 (羧酸) 羧酸可為脂肪族羧酸，亦可為芳香族羧酸。又，羧酸可為具有1個羧基之一元羧酸，亦可為具有2個以上羧基之多元羧酸。 又，羧酸之碳原子數並無特別限定，較佳為1～50，更佳為1～30。 作為羧酸之較佳之具體例，可列舉：甲酸、乙酸、丙酸、丁酸、戊酸、己酸、庚酸、辛酸、壬酸、癸酸、乳酸、丙烯酸、及甲基丙烯酸等脂肪族單羧酸；草酸、順丁烯二酸、己二酸、癸二酸、壬二酸、反丁烯二酸、及伊康酸等脂肪族多元羧酸；苯甲酸、水楊酸、對羥基苯甲酸、間羥基苯甲酸、鄰氯苯甲酸、對氯苯甲酸、間氯苯甲酸、鄰甲基苯甲酸、對甲基苯甲酸、間甲基苯甲酸、對苯二甲酸、間苯二甲酸、鄰苯二甲酸、2,6-萘二羧酸、1,4-萘二羧酸、4,4'-二羧基聯苯、4,4'-二羧基二苯基醚、及偏苯三甲酸等芳香族羧酸。 又，作為羧酸，亦較佳為具有芳香族基、與和伸烷基鍵結之羧基的化合物。作為此種化合物之具體例，可列舉：苯基乙酸、3-苯基丙酸、4-苯基丁酸等。 又，於本實施形態中，作為較佳地使用之羧酸，例如可列舉下式(b1-1)所表示之化合物。 [化10]

(式(b1-1)中，R ^b0、R ^b1及R ^b2各自獨立為氫原子、鹵素原子、羥基、巰基、硫醚基(sulfide group)、矽烷基、矽烷醇基、硝基、亞硝基、亞磺酸基(sulfino group)、磺基、磺酸基(sulfonato group)、膦基(phosphino group)、氧膦基(phosphinyl group)、膦醯基(phosphono group)、膦酸基(phosphonato group)、或有機基，R ^b0及R ^b1中之任一者為可具有取代基之芳香族基、或烷基) 作為式(b1-1)中之有機基，可列舉：烷基、鏈烯基、環烷基、環烯基、芳基、芳烷基等。對於該有機基，亦可於該有機基中含有雜原子等烴基以外之鍵或取代基。又，該有機基可為直鏈狀、支鏈狀、環狀中之任一者。該有機基通常為1價，但於形成環狀結構之情形等時，可成為2價以上之有機基。 有機基所含之鍵只要無損本發明之效果，則無特別限定，有機基亦可包含含有氧原子、氮原子、矽原子等雜原子之鍵。作為含有雜原子之鍵之具體例，可列舉：醚鍵、硫醚鍵、羰基鍵、硫羰基鍵、酯鍵、醯胺鍵、胺基甲酸酯鍵、亞胺基鍵(-N＝C(-R)-、-C(＝NR)-：R表示氫原子或有機基)、碳酸酯鍵、磺醯基鍵、亞磺醯基鍵、偶氮鍵等。 作為有機基可具有之含有雜原子之鍵，就式(b1-1)所表示之化合物之耐熱性之觀點而言，較佳為醚鍵、硫醚鍵、羰基鍵、硫羰基鍵、酯鍵、醯胺鍵、胺基甲酸酯鍵、亞胺基鍵(-N＝C(-R)-、-C(＝NR)-：R表示氫原子或1價有機基)、碳酸酯鍵、磺醯基鍵、亞磺醯基鍵。 作為R ^b0、R ^b1及R ^b2之具體例，可列舉：鹵素原子、羥基、巰基、硫醚基、氰基、異氰基、氰酸基(cyanato group)、異氰酸基(isocyanato group)、硫氰酸基(thiocyanato group)、異硫氰酸基(isothiocyanato group)、矽烷基、矽烷醇基、烷氧基、烷氧基羰基、胺基甲醯基、硫代胺基甲醯基、硝基、亞硝基、羧酸基(carboxylate group)、醯基、醯氧基、亞磺酸基、磺酸基、膦基、氧膦基、膦酸基、烷基醚基、鏈烯基醚基、烷基硫醚基、鏈烯基硫醚基、芳基醚基、芳基硫醚基等。上述取代基所含之氫原子可被取代為烴基。又，上述取代基所含之烴基可為直鏈狀、支鏈狀、及環狀中之任一者。 式(b1-1)中，R ^b0及R ^b1中之任一者為可具有取代基之芳香族基、或烷基。式(b1-1)中，於R ^b0及R ^b1中之任一者為烷基之情形時，該烷基可為直鏈狀，亦可為支鏈狀。該烷基之碳原子數較佳為1～20，更佳為1～15，尤佳為1～10，進而較佳為1～6，最佳為1～4。 亦有R ^b2為烷基之情形，該情形時之烷基較佳為與上述相同之基。 式(b1-1)中，於R ^b0及R ^b1中之任一者為可具有取代基之芳香族基之情形時，該芳香族基可具有之取代基之種類於不妨礙本發明之目的之範圍內並無特別限定。作為該取代基之適宜例，可列舉：鹵素原子、羥基、巰基、硫醚基、矽烷基、矽烷醇基、硝基、亞硝基、磺酸基、膦基、氧膦基、膦酸基、或有機基。 式(b1-1)中，於R ^b0及R ^b1中之任一者為可具有取代基之芳香族基之情形時，芳香族基可為芳香族烴基，亦可為芳香族雜環基，較佳為芳香族烴基。作為芳香族基之適宜例，可列舉：苯基、萘基、聯苯基、蒽基、及菲基。該等芳香族基中，較佳為苯基。 亦有R ^b2為可具有取代基之芳香族基之情形，該情形時之可具有取代基之芳香族基較佳為與上述相同之基。 芳香族基可具有之取代基之具體例與R ^b0、R ^b1及R ^b2之具體例相同。 式(b1-1)所表示之化合物中，作為較佳為之化合物，可列舉下式(b1-2)所表示之化合物。 [化11]

(式(b1-2)中，R ^b1及R ^b2各自獨立地表示氫原子、鹵素原子、羥基、巰基、硫醚基、矽烷基、矽烷醇基、硝基、亞硝基、亞磺酸基、磺基、磺酸基、膦基、氧膦基、膦醯基、膦酸基、或有機基；R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7各自獨立地表示氫原子、鹵素原子、羥基、巰基、硫醚基、矽烷基、矽烷醇基、硝基、亞硝基、亞磺酸基、磺基、磺酸基、膦基、氧膦基、膦醯基、膦酸基、胺基、銨基、或有機基；R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7中之2個以上亦可鍵結而形成環狀結構，R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7亦可含有雜原子之鍵) R ^b1及R ^b2中之有機基與針對式(b1-1)所說明之有機基相同。 以上之中，作為式(b1-2)中之R ^b1及R ^b2，各自獨立地較佳為氫原子、碳原子數1～10之烷基、碳原子數4～13之環烷基、碳原子數4～13之環烯基、碳原子數7～16之芳基氧基烷基、碳原子數7～20之芳烷基、具有氰基之碳原子數2～11之烷基、具有羥基之碳原子數1～10之烷基、碳原子數1～10之烷氧基、碳原子數2～11之醯胺基、碳原子數1～10之烷基硫基、碳原子數1～10之醯基、碳原子數6～20之芳基、取代有供電子性基及/或吸電子性基之碳原子數6～20之芳基、取代有供電子性基及/或吸電子性基之苄基、氰基、甲硫基。更佳為R ^b1及R ^b2兩者均為氫原子，或者R ^b1為甲基，R ^b2為氫原子。 作為R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7中之有機基，可列舉R ^b1及R ^b2中所例示之基。關於該有機基，與R ^b1及R ^b2之情形同樣地亦可於該有機基中含有雜原子等烴基以外之鍵或取代基。又，該有機基可為直鏈狀、支鏈狀、環狀中之任一者。 關於R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7，其等中之2個以上亦可鍵結而形成環狀結構，亦可含有雜原子之鍵。作為環狀結構，可列舉雜環烷基、雜芳基等，亦可為縮合環。例如，R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7中之2個以上亦可鍵結，共用R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7所鍵結之苯環之原子而形成萘、蒽、菲、茚等縮合環。 以上之中，作為R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7，各自獨立地較佳為氫原子、碳原子數1～10之烷基、碳原子數4～13之環烷基、碳原子數4～13之環烯基、碳原子數7～16之芳基氧基烷基、碳原子數7～20之芳烷基、具有氰基之碳原子數2～11之烷基、具有羥基之碳原子數1～10之烷基、碳原子數1～10之烷氧基、碳原子數2～11之醯胺基、碳原子數1～10之烷基硫基、碳原子數1～10之醯基、碳原子數2～11之酯基、碳原子數6～20之芳基、取代有供電子性基及/或吸電子性基之碳原子數6～20之芳基、取代有供電子性基及/或吸電子性基之苄基、氰基、甲硫基、硝基。 又，作為R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7，亦較佳為其等中之2個以上進行鍵結，共用R ^b3、R ^b4、R ^b5、R ^b6、及R ^b7所鍵結之苯環之原子而形成萘、蒽、菲、茚等縮合環之情形。 上述式(b1-2)所表示之化合物中，較佳為下式(b1-3)所表示之化合物。 [化12]

(式(b1-3)中，R ^b1～R ^b6係與式(b1-2)相同；R ^b8表示氫原子或有機基；R ^b3及R ^b4不成為羥基；R ^b3、R ^b4、R ^b5、及R ^b6中之2個以上亦可鍵結而形成環狀結構，亦可含有雜原子之鍵) 式(b1-3)所表示之化合物具有取代基-O-R ^b8，因此容易均一地分散或溶解於樹脂組合物中。 式(b1-3)中，R ^b8為氫原子或有機基。於R ^b8為有機基之情形時，作為有機基，可列舉R ^b1及R ^b2中所例示之基。該有機基亦可於該有機基中含有雜原子。又，該有機基可為直鏈狀、支鏈狀、環狀中之任一者。作為R ^b8，較佳為氫原子、或碳原子數1～12之烷基，更佳為甲基。 式(b1-1)所表示之化合物中之尤佳化合物之具體例如下所示。 [化13]

(羧酸酯) 羧酸酯只要為具有酯鍵之化合物即可，並無特別限定。羧酸酯亦可具有芳香族基。 作為羧酸酯，例如可列舉上述羧酸之下述酯：C ₁-C ₁₀烷基酯、C ₃-C ₁₀環烷基酯、苯基酯、C ₆-C ₁₀之烷基苯基酯、C ₇-C ₁₀之烷氧基苯基酯、萘基酯、C ₇-C ₁₀之芳烷基酯等。 於羧酸酯為多元羧酸之酯之情形時，羧酸酯可同時具有酯鍵與羧基。例如，對苯二甲酸單甲酯等亦為羧酸酯。 作為羧酸酯之較佳之具體例，可列舉：甲酸甲酯、甲酸乙酯、甲酸正丙酯、甲酸異丙酯、甲酸正丁酯、甲酸異丁酯、甲酸第二丁酯、甲酸第三丁酯、甲酸正戊酯、甲酸正己酯、甲酸正庚酯、甲酸正辛酯、甲酸環丙酯、甲酸環丁酯、甲酸環戊酯、甲酸環己酯、甲酸環庚酯、甲酸環辛酯、甲酸苯酯、甲酸鄰甲苯酯、甲酸間甲苯酯、甲酸對甲苯酯、甲酸α-萘基酯、甲酸β-萘基酯、甲酸苄酯、及甲酸苯乙酯等甲酸酯； 乙酸甲酯、乙酸乙酯、乙酸正丙酯、乙酸異丙酯、乙酸正丁酯、乙酸異丁酯、乙酸第二丁酯、乙酸第三丁酯、乙酸正戊酯、乙酸正己酯、乙酸正庚酯、乙酸正辛酯、乙酸環丙酯、乙酸環丁酯、乙酸環戊酯、乙酸環己酯、乙酸環庚酯、乙酸環辛酯、乙酸苯酯、乙酸鄰甲苯酯、乙酸間甲苯酯、乙酸對甲苯酯、乙酸α-萘基酯、乙酸β-萘基酯、乙酸苄酯、及乙酸苯乙酯等乙酸酯； 丙酸甲酯、丙酸乙酯、丙酸正丙酯、丙酸異丙酯、丙酸正丁酯、丙酸異丁酯、丙酸第二丁酯、丙酸第三丁酯、丙酸正戊酯、丙酸正己酯、丙酸正庚酯、丙酸正辛酯、丙酸環丙酯、丙酸環丁酯、丙酸環戊酯、丙酸環己酯、丙酸環庚酯、丙酸環辛酯、丙酸苯酯、丙酸鄰甲苯酯、丙酸間甲苯酯、丙酸對甲苯酯、丙酸α-萘基酯、丙酸β-萘基酯、丙酸苄酯、及丙酸苯乙酯等丙酸酯； 丙烯酸甲酯、丙烯酸乙酯、丙烯酸正丙酯、丙烯酸異丙酯、丙烯酸正丁酯、丙烯酸異丁酯、丙烯酸第二丁酯、丙烯酸第三丁酯、丙烯酸正戊酯、丙烯酸正己酯、丙烯酸正庚酯、丙烯酸正辛酯、丙烯酸環丙酯、丙烯酸環丁酯、丙烯酸環戊酯、丙烯酸環己酯、丙烯酸環庚酯、丙烯酸環辛酯、丙烯酸苯酯、丙烯酸鄰甲苯酯、丙烯酸間甲苯酯、丙烯酸對甲苯酯、丙烯酸α-萘基酯、丙烯酸β-萘基酯、丙烯酸苄酯、及丙烯酸苯乙酯等丙烯酸酯； 甲基丙烯酸甲酯、甲基丙烯酸乙酯、甲基丙烯酸正丙酯、甲基丙烯酸異丙酯、甲基丙烯酸正丁酯、甲基丙烯酸異丁酯、甲基丙烯酸第二丁酯、甲基丙烯酸第三丁酯、甲基丙烯酸正戊酯、甲基丙烯酸正己酯、甲基丙烯酸正庚酯、甲基丙烯酸正辛酯、甲基丙烯酸環丙酯、甲基丙烯酸環丁酯、甲基丙烯酸環戊酯、甲基丙烯酸環己酯、甲基丙烯酸環庚酯、甲基丙烯酸環辛酯、甲基丙烯酸苯酯、甲基丙烯酸鄰甲苯酯、甲基丙烯酸間甲苯酯、甲基丙烯酸對甲苯酯、甲基丙烯酸α-萘基酯、甲基丙烯酸β-萘基酯、甲基丙烯酸苄酯、及甲基丙烯酸苯乙酯等甲基丙烯酸酯； 苯甲酸甲酯、苯甲酸乙酯、苯甲酸正丙酯、苯甲酸異丙酯、苯甲酸正丁酯、苯甲酸異丁酯、苯甲酸第二丁酯、苯甲酸第三丁酯、苯甲酸正戊酯、苯甲酸正己酯、苯甲酸正庚酯、苯甲酸正辛酯、苯甲酸環丙酯、苯甲酸環丁酯、苯甲酸環戊酯、苯甲酸環己酯、苯甲酸環庚酯、苯甲酸環辛酯、苯甲酸苯酯、苯甲酸鄰甲苯酯、苯甲酸間甲苯酯、苯甲酸對甲苯酯、苯甲酸α-萘基酯、苯甲酸β-萘基酯、苯甲酸苄酯、及苯甲酸苯乙酯等苯甲酸酯； 對苯二甲酸二甲酯、對苯二甲酸二乙酯、對苯二甲酸二正丙酯、對苯二甲酸二異丙酯、對苯二甲酸二正丁酯、對苯二甲酸二異丁酯、對苯二甲酸二第二丁酯、對苯二甲酸二第三丁酯、對苯二甲酸二正戊酯、對苯二甲酸二正己酯、對苯二甲酸二正庚酯、對苯二甲酸二正辛酯、對苯二甲酸二環丙酯、對苯二甲酸二環丁酯、對苯二甲酸二環戊酯、對苯二甲酸二環己酯、對苯二甲酸二環庚酯、對苯二甲酸二環辛酯、對苯二甲酸二苯酯、對苯二甲酸二鄰甲苯酯、對苯二甲酸二間甲苯酯、對苯二甲酸二對甲苯酯、對苯二甲酸二(α-萘基)酯、對苯二甲酸二(β-萘基)酯、對苯二甲酸二苄酯、及對苯二甲酸二苯乙酯等對苯二甲酸二酯； 乙二醇單乙酸酯、乙二醇單丙酸酯、乙二醇單丁酸酯、乙二醇單戊酸酯、乙二醇單苯甲酸酯、乙二醇二乙酸酯、乙二醇二丙酸酯、乙二醇二丁酸酯、乙二醇二戊酸酯、及乙二醇二苯甲酸酯等乙二醇酯； 二乙二醇單乙酸酯、二乙二醇單丙酸酯、二乙二醇單丁酸酯、二乙二醇單戊酸酯、二乙二醇單苯甲酸酯、二乙二醇二乙酸酯、二乙二醇二丙酸酯、二乙二醇二丁酸酯、二乙二醇二戊酸酯、及二乙二醇二苯甲酸酯等二乙二醇酯； 丙二醇單乙酸酯、丙二醇單丙酸酯、丙二醇單丁酸酯、丙二醇單戊酸酯、丙二醇單苯甲酸酯、丙二醇二乙酸酯、丙二醇二丙酸酯、丙二醇二丁酸酯、丙二醇二戊酸酯、及丙二醇二苯甲酸酯等丙二醇酯； 二丙二醇單乙酸酯、二丙二醇單丙酸酯、二丙二醇單丁酸酯、二丙二醇單戊酸酯、二丙二醇單苯甲酸酯、二丙二醇二乙酸酯、二丙二醇二丙酸酯、二丙二醇二丁酸酯、二丙二醇二戊酸酯、及二丙二醇二苯甲酸酯等二丙二醇酯。 又，作為羧酸酯，亦較佳為上述之式(b1-1)所表示之羧酸之下述酯：甲酯、乙酯、正丙酯、異丙酯、正丁酯、異丁酯、第二丁酯、第三丁酯、正戊酯、正己酯、正庚酯、正辛酯、環丙酯、環丁酯、環戊酯、環己酯、環庚酯、環辛酯、苯酯、鄰甲苯酯、間甲苯酯、對甲苯酯、α-萘基酯、β-萘基酯、苄酯、及苯乙酯。 (羧酸酐) 羧酸酐只要為具有羧酸酐基(-CO-O-CO-)之化合物，則無特別限定。 作為羧酸酐之適宜例，可列舉：乙酸酐、丙酸酐、丁酸酐、苯甲酸酐、鄰苯二甲酸酐、萘二羧酸酐、琥珀酸酐、氯橋酸酐、納迪克酸酐(himic anhydride)、順丁烯二酸酐、四氫鄰苯二甲酸酐、六氫鄰苯二甲酸酐、四溴鄰苯二甲酸酐、四氯鄰苯二甲酸酐、偏苯三甲酸酐、均苯四甲酸酐、二苯甲酮四羧酸酐、2,3,6,7-萘四羧酸二酐、及5-(2,5-側氧基四氫呋喃基)-3-甲基-3-環己烯-1,2-二羧酸酐、及苯乙烯-順丁烯二酸酐共聚物等。 (碳酸酯) 碳酸酯只要為具有碳酸酯鍵(-O-CO-O-)之化合物，則無特別限定。碳酸酯可為碳酸二甲酯之類的鏈狀碳酸酯，亦可為碳酸乙二酯之類的環狀碳酸酯。 作為碳酸酯化合物之較佳之具體例，可列舉：碳酸二甲酯、碳酸二乙酯、碳酸二正丙酯、碳酸二異丙酯、碳酸二苯酯、碳酸乙二酯、及碳酸丙二酯等。 以上所說明之羰基氧基化合物(B1)中，尤佳為下式(b1)所表示之化合物。 [化14]

(式(b1)中，R ^b0為烷基、或可具有取代基之芳香族基，R ^b9為氫原子、或烷基。) 於R ^b9為烷基之情形時，該烷基與上述式(b1-1)中之R ^b0之烷基相同。 又，於本實施形態中，就能夠將聚醯胺酸(A)以適當之速度轉化為聚醯亞胺之觀點而言，R ^b9尤佳為氫原子。 [鹼性含氮化合物(B2)] 鹼性含氮化合物(B2)只要為含有氮原子且顯示出布忍斯特定義中之鹼性之化合物，則無特別限定。 作為鹼性含氮化合物(B2)，例如可列舉：氨、甲胺、乙胺、正丙胺、異丙胺、異丁胺、正丁胺、正戊胺、正己胺、二甲胺、二乙胺、二正丙胺、二異丙胺、二異丁胺、二正丁胺、二正戊胺、二正己胺、三甲胺、三乙胺、三正丙胺、三異丙胺、三異丁胺、三正丁胺、三正戊胺、三正己胺、苯胺、鄰甲苯胺、間甲苯胺、對甲苯胺、α-萘胺、β-萘胺、及鄰苯二胺、間苯二胺、對苯二胺等非環式胺類。 又，胍、胺基吡啶、胺基烷基吡啶、胺基吡咯烷、吲唑、咪唑、吡唑、吡𠯤、嘧啶、嘌呤、咪唑啉、吡唑啉、哌𠯤、胺基嗎啉、及胺基烷基嗎啉等作為鹼性含氮化合物(B2)亦較佳。 上述化合物亦可具有取代基，作為較佳之取代基，可列舉：胺基、胺基烷基、烷基胺基、胺基芳基、芳基胺基、烷基、烷氧基、醯基、醯氧基、芳基、芳基氧基、硝基、羥基、氰基等。 作為尤佳之有機鹼性化合物(B2)，可列舉：胍、1,1-二甲基胍、1,1,3,3-四甲基胍、咪唑、2-甲基咪唑、4-甲基咪唑、N-甲基咪唑、2-苯基咪唑、4,5-二苯基咪唑、2,4,5-三苯基咪唑、2-胺基吡啶、3-胺基吡啶、4-胺基吡啶、2-二甲基胺基吡啶、4-二甲基胺基吡啶、2-二乙基胺基吡啶、2-(胺基甲基)吡啶、2-胺基-3-甲基吡啶、2-胺基-4-甲基吡啶、2-胺基-5-甲基吡啶、2-胺基-6-甲基吡啶、3-胺基乙基吡啶、4-胺基乙基吡啶、3-胺基吡咯烷、哌𠯤、N-(2-胺基乙基)哌𠯤、N-(2-胺基乙基)哌啶、4-胺基-2,2,6,6-四甲基哌啶、4-哌啶基哌啶、2-亞胺基哌啶、1-(2-胺基乙基)吡咯烷、吡唑、3-胺基-5-甲基吡唑、5-胺基-3-甲基-1-對甲苯基吡唑、吡𠯤、2-(胺基甲基)-5-甲基吡𠯤、嘧啶、2,4-二胺基嘧啶、4,6-二羥基嘧啶、2-吡唑啉、3-吡唑啉、N-胺基嗎啉、N-(2-胺基乙基)嗎啉、及1,8-二氮雜雙環[5.4.0]-7-十一碳烯等。 以上，對鹼性含氮化合物(B2)進行了說明，鹼性含氮化合物(B2)中，就促進聚醯胺酸(A)之硬化之效果較高之方面而言，較佳為含有咪唑環之咪唑化合物。此種咪唑化合物典型而言以下式(b2-1)表示。 [化15]

(式(b2-1)中，R ^b10、R ^b11、及R ^b12各自獨立為氫原子、鹵素原子、羥基、巰基、硫醚基、矽烷基、矽烷醇基、硝基、亞硝基、磺酸基、膦基、氧膦基、膦酸基、或有機基) 作為式(b2-1)中R ^b10、R ^b11、及R ^b12中之有機基，可列舉：烷基、鏈烯基、環烷基、環烯基、芳基、芳烷基等。關於該有機基，可於該有機基中含有雜原子等烴基以外之鍵或取代基。又，該有機基可為直鏈狀、支鏈狀、環狀中之任一者。該有機基通常為1價，於形成環狀結構之情形等時，可成為2價以上之有機基。 式(b2-1)中之R ^b10、R ^b11、及R ^b12中之有機基與式(b1-1)中之有機基相同。 作為R ^b10、R ^b11、及R ^b12，較佳為氫原子、碳原子數1～12之烷基、碳原子數1～12之芳基、碳原子數1～12之烷氧基、及鹵素原子，更佳為氫原子。 樹脂組合物中之羰基氧基化合物(B1)之含量與鹼性含氮化合物(B2)之含量之總量於不妨礙本發明之目的之範圍內並無特別限定，相對於100質量份聚醯胺酸(A)，上述總量較佳為0.01～30質量份，更佳為0.05～25質量份，尤佳為0.2～20質量份。 又，於將羰基氧基化合物(B1)與鹼性含氮化合物(B2)併用之情形時，羰基氧基化合物(B1)之質量W _B1與鹼性含氮化合物(B2)之質量W _B2之比率W _B1/W _B2較佳為1/99～99/1，更佳為5/95～95/5，尤佳為15/85～85/15。 ＜溶劑(S)＞ 就塗佈性之方面而言，樹脂組合物較佳為含有溶劑(S)。樹脂組合物可為含有固體之糊劑，亦可為溶液，較佳為溶液。溶劑(S)可以單獨使用，或將2種以上混合而使用。 溶劑(S)之種類於不妨礙本發明之目的之範圍內並無特別限定。溶劑(S)之適宜例與上述之於四羧酸二酐與二胺化合物之反應中所使用之溶劑之例子相同。 又，溶劑(S)亦可含有聚乙二醇、乙二醇、二乙二醇、丙二醇、及二丙二醇等醇系溶劑。於溶劑(S)含有醇系溶劑之情形時，容易形成耐熱性優異之硬化物。 又，溶劑(S)亦可使用含有下式(5)所表示之化合物(S1)的溶劑。 [化16]

(式(5)中，R ^S1及R ^S2各自獨立為碳原子數1～3之烷基，R ^S3為下式(5-1)或下式(5-2)所表示之基， [化17]

式(5-1)中，R ^S4為氫原子或羥基，R ^S5及R ^S6各自獨立為碳原子數1～3之烷基；式(5-2)中，R ^S7及R ^S8各自獨立為氫原子、或碳原子數1～3之烷基) 式(5)所表示之化合物(S1)中，作為R ^S3為式(5-1)所表示之基之情形之具體例，可列舉：N,N,2-三甲基丙醯胺、N-乙基-N,2-二甲基丙醯胺、N,N-二乙基-2-甲基丙醯胺、N,N,2-三甲基-2-羥基丙醯胺、N-乙基-N,2-二甲基-2-羥基丙醯胺、及N,N-二乙基-2-羥基-2-甲基丙醯胺等。 式(5)所表示之化合物(S1)中，作為R ^S3為式(5-2)所表示之基之情形之具體例，可列舉：N,N,N',N'-四甲基脲、N,N,N',N'-四乙基脲等。 上述之化合物(S1)之例中，作為尤佳例，較佳為N,N,2-三甲基丙醯胺、及N,N,N',N'-四甲基脲。 於樹脂組合物含有溶劑(S)之情形時，溶劑(S)中之上述化合物(S1)之含量於不妨礙本發明之目的之範圍內並無特別限定。關於化合物(S1)相對於溶劑之質量之比率，典型而言，相對於溶劑(S)之總量較佳為70質量%以上，更佳為80質量%以上，尤佳為90質量%以上，最佳為100質量%。 作為能夠與化合物(S1)一併使用之有機溶劑，可列舉：N,N-二甲基甲醯胺、N,N-二甲基乙醯胺、N-甲基-2-吡咯啶酮、六甲基磷醯胺、1,3-二甲基-2-咪唑啉酮等含氮極性溶劑；甲基乙基酮、甲基異丁基酮、環己酮、及異佛爾酮等酮類；二㗁烷、及四氫呋喃等環狀醚類；甲苯、及二甲苯等芳香族烴類；二甲基亞碸等亞碸類。 樹脂組合物中之溶劑(S)之含量於不妨礙本發明之目的之範圍內並無特別限定。樹脂組合物中之溶劑(S)之含量可根據樹脂組合物中之固形物成分含量而適當調整。樹脂組合物中之固形物成分含量較佳為5～70質量%，更佳為10～60質量%。 ＜其他成分＞ 於不妨礙本發明之目的之範圍內，樹脂組合物亦可含有上述成分以外之其他成分。作為其他成分之例子，可列舉：界面活性劑、塑化劑、黏度調整劑、消泡劑、及著色劑等。 ≪硬化物之製造方法≫ 第2態樣之硬化物之製造方法包括下述步驟： 塗膜形成步驟，於基材上塗佈第1態樣之樹脂組合物而形成塗膜；及 加熱步驟，於70～550℃下對塗膜進行加熱。 該方法中，由於使用第1態樣之樹脂組合物而形成了塗膜，故而會穩定地生成含有聚醯亞胺之硬化物。 其結果為，可獲得具有凹凸、翹曲或裂紋較少之平滑表面而外觀優異之硬化物。 ＜塗膜形成步驟＞ 於形成步驟中，於基材之表面塗佈第1態樣之樹脂組合物，而形成塗膜。作為塗佈方法，例如可列舉：浸塗法、噴霧法、棒塗法、輥塗法、旋塗法、淋幕式塗佈法等。 於塗佈後，基於促進從塗膜中排氣、去除溶劑(S)之目的，可將塗膜置於減壓氛圍中。減壓氛圍之真空度並無特別限定，較佳為300 Pa以下，更佳為150 Pa以下，進而較佳為100 Pa以下。 塗膜之厚度並無特別限定。典型而言，塗膜之厚度較佳為2～100 μm，更佳為3～50 μm。塗膜之厚度可藉由對塗佈方法、樹脂組合物之固形物成分濃度或黏度進行調節而適當地加以控制。 基材之材質只要於加熱塗佈膜時不會發生熱劣化與變形，則無特別限定。基材之形狀只要能夠塗佈樹脂組合物，則並無特別限定。作為基材之例子，可列舉：形成有欲絕緣之電極及/或配線之半導體元件等電子元件或多層配線基板等中間製品、或者各種基板。作為基體為基板之情形時之較佳之基板材質，可列舉：玻璃；矽；鋁(Al)；鋁-矽(Al-Si)、鋁-銅(Al-Cu)、鋁-矽-銅(Al-Si-Cu)等鋁合金；鈦(Ti)；鈦-鎢(Ti-W)等鈦合金；氮化鈦(TiN)；鉭(Ta)；氮化鉭(TaN)；鎢(W)；氮化鎢(WN)；銅。 又，於低溫下對塗膜進行加熱之情形時，亦可使用包含聚對苯二甲酸乙二酯(PET)或聚對苯二甲酸丁二酯(PBT)等樹脂之耐熱性較低之基材。 ＜加熱步驟＞ 塗膜形成步驟中所形成之塗膜係於加熱步驟中於70～550℃下進行加熱。 於加熱上述塗膜之情形時，加熱溫度例如可設定為120～500℃，較佳為150～450℃。藉由在上述範圍之溫度下加熱塗膜，能夠抑制所生成之聚醯亞胺之熱劣化與熱分解，並且穩定地生成硬化物。 又，於高溫下對塗膜進行加熱之情形時，有耗費大量能量、促進高溫下之處理設備之經時劣化之情況，因此於低於上述溫度之溫度下對塗膜進行加熱亦為較佳態樣。 加熱時間雖然亦取決於樹脂組合物之組成或塗膜之厚度等，但可設定為：下限值例如為5分鐘，較佳為10分鐘，更佳為20分鐘；上限值例如為4小時，較佳為3小時，更佳為2.5小時。 又，就降低聚醯亞胺之黃色指數之觀點、或更順利地從聚醯胺酸(A)轉化為聚醯亞胺之觀點而言，可對加熱時之氛圍(氧氣濃度等氣體組成)進行調整，或者亦可於加熱時或加熱前後組合減壓步驟。 [實施例] 以下，揭示實施例而更具體地說明本發明，但本發明之範圍並不限於該等實施例。 [聚醯胺酸(A)之製備] 向具備攪拌機、攪拌葉片、回流冷凝器、氮氣導入管之可分離式燒瓶中裝入以下所示之結構之四羧酸二酐與N-甲基-2-吡咯啶酮，從氮氣導入管向燒瓶中導入氮氣，使燒瓶內成為氮氣氛圍。繼而，將燒瓶浸於冰浴中，一邊攪拌內容物，一邊緩慢地滴加相對於四羧酸二酐為1.0莫耳量之對苯二胺之N-甲基-2-吡咯啶酮溶液。 滴加結束後，於50℃下反應20小時，而獲得含有聚醯胺酸(A)之溶液。再者，以下所示之結構之四羧酸二酐係依據國際公開第2011/099518號之合成例1、實施例1及實施例2中所記載之方法而製備，又，此處之溶液製備係以所獲得之聚醯胺酸(A)之固形物成分濃度成為15質量%之方式加以調整。 [化18]

[實施例1-3、比較例1] 於實施例1-3中，向如此而獲得之聚醯胺酸(A)之溶液中添加表1所示之添加劑，而製成樹脂組合物。表1中，括號內所示之值(質量%)為添加劑之量相對於聚醯胺酸(A)之量的比例。 另一方面，於比較例1中，未對上述所獲得之聚醯胺酸(A)之溶液添加任何添加劑。 再者，對甲氧基肉桂酸係使用東京化成工業股份有限公司所製造者，咪唑係使用岸田化學股份有限公司所製造者。 [製膜性評價] 針對如此而獲得之各種樹脂組合物，依據以下方式進行製膜性之評價。即，首先，於玻璃基材上塗佈各樹脂組合物，並減壓至13 Pa。暫時恢復至常壓後，於空氣(Air)條件下於80℃下加熱10分鐘，繼而於氧氣濃度為100 ppm之條件下於360℃下加熱30分鐘，而獲得膜厚為15 μm之硬化物。 針對如此而獲得之硬化物，藉由目視觀察是否形狀良好地製膜。再者，評價係依據以下之基準進行。 ◎：藉由目視進行確認，未觀察到粗糙。 ○：形成有大致平滑之膜，但於邊緣部分觀察到翹曲。 △：觀察到於膜之一部分產生裂紋。 ×：觀察到膜之各處均產生裂紋。 [表1] 表1    實施例1 實施例2 實施例3 比較例1 添加劑 ·對甲氧基肉桂酸(3質量%) ·咪唑(2質量%) ·對甲氧基肉桂酸(5質量%) ·咪唑(5質量%) - 製膜性評價 ◎ △ ○ × 由表1得知，藉由向聚醯胺酸(A)中添加特定之添加劑，而獲得製膜性優異、能夠穩定地形成含有聚醯亞胺之硬化物的樹脂組合物。 ≪Resin composition≫ The resin composition according to the first aspect of the present invention contains polyamic acid (A) having a structural unit represented by the following formula (a1), and One or more of the group consisting of a carbonyloxy compound (B1) and a basic nitrogen-containing compound (B2) without a -CO-O- bond in the molecule. [Chem 2]

(In formula (a1), A is a tetravalent organic group with 6 to 50 carbon atoms, and B is a divalent organic group) Here, the carbonyloxy compound (B1) having a -CO-O- bond in the molecule, and The basic nitrogen-containing compound (B2) (hereinafter, sometimes referred to as "carbonyloxy compound (B1)" or "basic nitrogen-containing compound (B2)") that does not have a -CO-O- bond in the molecule has The effect of promoting the transformation of polyamide acid (A) into polyimide resin. Therefore, when the resin composition is heated, the imidization of the polyamic acid (A) proceeds uniformly and rapidly, and as a result, unevenness, warpage, cracks, etc. are less likely to occur on the surface of the cured product, and a smooth surface can be formed. Hardened product with excellent surface and appearance. As described above, the above-mentioned resin composition cures at an appropriate speed, and stably provides a cured product containing a polyimide resin. Hereinafter, the essential or optional components contained in the resin composition will be described. <Polyamic acid (A)> The resin composition contains polyamic acid (A). Polyamic acid (A) is a polyimide precursor polymer produced when the resin composition is hardened. Polyamide acid has a structural unit represented by the following formula (a1). [Chem 3]

(In formula (a1), A is a tetravalent organic group with 6 to 50 carbon atoms, and B is a divalent organic group.) The above-mentioned polyamic acid (A) is usually prepared by combining tetracarboxylic dianhydride and diamine compound. obtained by condensation. Hereinafter, the tetracarboxylic dianhydride used in the manufacture of polyamic acid (A), the diamine compound, and the manufacturing method of polyamic acid (A) are demonstrated. [Tetracarboxylic dianhydride] The tetracarboxylic dianhydride which generates the structural unit represented by the formula (a1) is represented by the following formula (a1-1). The tetracarboxylic dianhydride represented by formula (a1-1) reacts with the following diamine compound, and produces the polyamic acid (A) which has the structural unit represented by formula (a1). This tetracarboxylic dianhydride may be used individually by 1 type, and may use it in combination of 2 or more types. [chemical 4]

(In formula (a1-1), A is a tetravalent organic group with 6 to 50 carbon atoms) In formula (a1-1), A is a tetravalent organic group with 6 to 50 carbon atoms. In addition to the acid anhydride groups represented by the two -CO-O-CO- in -1), one or more substituents may be present. Suitable examples of substituents are preferably fluorine atoms, alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, fluorinated alkyl groups having 1 to 6 carbon atoms, The fluorinated alkoxy group of ~6 may also contain a carboxyl group or a carboxylate group in addition to the acid anhydride group represented by the formula (a1-1). When the substituent is a fluorinated alkyl group or a fluorinated alkoxy group, it is preferably a perfluoroalkyl group or a perfluoroalkoxy group. The above substituents are also the same for one or plural substituents that the aromatic group described below may have on the aromatic ring. In the formula (a1-1), A is a tetravalent organic group, the lower limit of the number of carbon atoms is 6, and the upper limit is 50. The number of carbon atoms constituting A is more preferably 8 or more, further preferably 12 or more. Moreover, the number of carbon atoms constituting A is more preferably 40 or less, and further preferably 30 or less. A may be an aliphatic group, an aromatic group, or a combination of these structures. A may contain halogen atoms, oxygen atoms, and sulfur atoms in addition to carbon atoms and hydrogen atoms. When A contains an oxygen atom, a nitrogen atom, or a sulfur atom, the oxygen atom, nitrogen atom, or sulfur atom can be selected from nitrogen-containing heterocyclic groups, -CONH-, -NH-, -N=N-, -CH =N-, -COO-, -O-, -CO-, -SO-, -SO ₂ -, -S-, and -SS- are contained in A, more preferably selected from - The forms of the groups among O-, -CO-, -SO-, -SO ₂ -, -S-, and -SS- are included in A. Tetracarboxylic dianhydrides can be appropriately selected from tetracarboxylic dianhydrides previously used as raw materials for polyamic acid synthesis. The tetracarboxylic dianhydride may be an aliphatic tetracarboxylic dianhydride or an aromatic tetracarboxylic dianhydride. Examples of aliphatic tetracarboxylic dianhydrides include 2,2-bis(3,4-dicarboxy)propane dianhydride, bis(3,4-dicarboxy)methane dianhydride, etc. ring structure. The alicyclic structure may also be polycyclic. As the polycyclic alicyclic structure, for example, structures having bridged alicyclic structures such as bicyclo[2.2.1]heptane, etc., such as bridged alicyclic structures It can also be condensed with other bridged alicyclic structures and/or non-bridged alicyclic structures, and the bridged alicyclic structures can also be condensed with other bridged alicyclic structures and/or non-bridged alicyclic structures structure to connect. When an aliphatic tetracarboxylic dianhydride is used, it tends to be easy to obtain a cured product excellent in transparency using a resin composition. Moreover, as an aliphatic group constituting A in formula (a1-1), for example, a tetravalent group represented by the following formula (a2) can be used. When such a base is used, a transparent polyimide film tends to be easily obtained. Furthermore, n in the formula (a2) is preferably 5 or less, more preferably 3 or less, from the viewpoint of ease of purification of the raw material compound. Also, n is preferably 1 or more, more preferably 2 or more, from the viewpoint of excellent chemical stability of the raw material compound capable of producing the structure represented by formula (a1). n in the formula (a2) is particularly preferably 2 or 3. [chemical 5]

(In formula (a2), R ^a11 , R ^a12 , and R ^a13 are each independently selected from the group consisting of a hydrogen atom, an alkyl group with 1 to 5 carbon atoms, and a fluorine atom, and n is 0 to 12 integer) Examples of aromatic tetracarboxylic dianhydrides include pyromelteric dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)phthalic anhydride, 3,3',4, 4'-Oxydiphthalic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 3, 3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenone tetracarboxylic dianhydride, etc. Moreover, what is represented by following general formula (a1-2)-(a1-4) may be sufficient as an aromatic tetracarboxylic dianhydride, for example. [chemical 6]

In the above formulas (a1-2) and (a1-3), each of R ^a1 , R ^a2 and R ^a3 is an aliphatic group which may be substituted with a halogen, an oxygen atom, a sulfur atom, or an aromatic group via one or more divalent elements. Any one of the group groups, or a divalent substituent composed of a combination thereof. R ^a2 and R ^a3 may be the same or different. That is, R ^a1 , R ^a2 and R ^a3 may also contain a carbon-carbon single bond, a carbon-oxygen-carbon ether bond or a halogen element (fluorine, chlorine, bromine, iodine), such as: 2,2-bis(3 ,4-dicarboxytrifluorophenoxy)propane dianhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)phthalic anhydride, 1,4-bis(3,4-dicarboxytri Fluorophenoxy)tetrachlorophthalic anhydride, 2,2',5,5',6,6'-hexafluoro-3,3',4,4',-biphenyltetracarboxylic dianhydride, etc. Also, in the above formula (a1-4), R ^a4 and R ^a5 are any of an aliphatic group that may be substituted with a halogen, an aromatic group that passes through one or more divalent elements, and a halogen, or represent The monovalent substituent formed by the combination of etc. may be the same or different, and difluoropyromelic dianhydride, dichloropyromelic dianhydride, etc. may be used. Examples of tetracarboxylic dianhydrides used to obtain fluorine-containing polyimides containing fluorine in the molecular structure include (trifluoromethyl)pyromelite dianhydride, bis(trifluoromethyl)pyromelite Pyromelite dianhydride, bis(heptafluoropropyl)pyromelite dianhydride, pentafluoroethyl pyromelite dianhydride, bis{3,5-bis(trifluoromethyl)phenoxy}pyromelite Acid dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 5,5'-bis(trifluoromethyl)-3,3',4,4'-tetracarboxy Biphenyldianhydride, 2,2',5,5'-tetrakis(trifluoromethyl)-3,3',4,4'-tetracarboxybiphenyldianhydride, 5,5'-bis(trifluoromethyl) base)-3,3',4,4'-tetracarboxydiphenyl ether dianhydride, 5,5'-bis(trifluoromethyl)-3,3',4,4'-tetracarboxybenzidine Ketone dianhydride, bis{(trifluoromethyl)dicarboxyphenoxy}phthalic anhydride, bis{(trifluoromethyl)dicarboxyphenoxy}(trifluoromethyl)phthalic anhydride, bis(dicarboxy Phenoxy)(trifluoromethyl)phthalic anhydride, bis(dicarboxyphenoxy)bis(trifluoromethyl)phthalic anhydride, bis(dicarboxyphenoxy)tetrakis(trifluoromethyl)benzenedi anhydride, 2,2-bis{4-(3,4-dicarboxyphenoxy)phenyl}hexafluoropropane dianhydride, bis{(trifluoromethyl)dicarboxyphenoxy}biphenyldianhydride, bis {(trifluoromethyl)dicarboxyphenoxy}bis(trifluoromethyl)biphenyl dianhydride, bis{(trifluoromethyl)dicarboxyphenoxy}diphenyl ether dianhydride, bis(dicarboxy Phenoxy)bis(trifluoromethyl)biphenyl dianhydride, difluoropyromelite dianhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorophthalic dianhydride, 1 , 4-bis(3,4-dicarboxytrifluorophenoxy) octafluorobiphenyl dianhydride, etc. As the tetracarboxylic dianhydride, when considering the heat resistance, tensile elongation and chemical resistance of the obtained film or molded article, it is preferable to use an aromatic tetracarboxylic dianhydride. It is preferable to use 3,3',4,4'-biphenyltetracarboxylic dianhydride and pyromelite dianhydride in terms of easy availability etc. In addition, acyl chlorides, esterified products, and the like of tetracarboxylic acids having the same basic skeleton as these can also be used. In this embodiment, tetracarboxylic dianhydride and dicarboxylic anhydride can also be used together. When the above-mentioned carboxylic acid anhydride is used in combination, the properties of the obtained imide ring-containing polymer such as polyimide resin may be further improved. Examples of dicarboxylic anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylendomethylene Tetrahydrophthalic anhydride, chlorendic anhydride, methyltetrahydrophthalic anhydride, glutaric anhydride, cis-4-cyclohexene-1,2-dicarboxylic anhydride, and the like. [Diamine Compound] As a diamine compound, typically, a compound represented by the following formula (a3-1) can be used. A diamine compound may be used individually by 1 type, and may use it in combination of 2 or more types. H ₂ NB-NH ₂ ... (a3-1) (In formula (a3-1), B represents a divalent organic group) In formula (a3-1), B is a divalent organic group, except for formula (a3-1 ) may have one or more substituents in addition to the two amino groups. Suitable examples of substituents are preferably fluorine atoms, alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, fluorinated alkyl groups having 1 to 6 carbon atoms, ~6 fluorinated alkoxy groups, hydroxyl groups. When the substituent is a fluorinated alkyl group or a fluorinated alkoxy group, it is preferably a perfluoroalkyl group or a perfluoroalkoxy group. In formula (a3-1), the lower limit of the number of carbon atoms in the organic group of B is preferably 2, more preferably 6, and the upper limit is preferably 50, more preferably 30. Although B may be an aliphatic group, it is preferably an organic group containing one or more aromatic rings. When B is an organic group containing one or more aromatic rings, the organic group may be one aromatic group itself, or two or more aromatic groups may be obtained through an aliphatic hydrocarbon group and a halogenated aliphatic hydrocarbon group, A group formed by bonds of heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms. Examples of bonds containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms included in B include -CONH-, -NH-, -N=N-, -CH=N-, -COO-, and -O- , -CO-, -SO-, -SO ₂ -, -S-, and -SS-, etc., preferably -O-, -CO-, -SO-, -SO ₂ -, -S-, and - SS-. The aromatic ring bonded to the amine group in B is preferably a benzene ring. When the ring bonded to the amine group in B is a condensed ring containing two or more rings, the ring bonded to the amine group in the condensed ring is preferably a benzene ring. In addition, the aromatic ring included in B may be an aromatic heterocyclic ring. When B is an organic group containing an aromatic ring, the organic group is preferably represented by the following formulas (1) to (4) in terms of the heat resistance of the cured product formed using the resin composition At least one of the bases. [chemical 7]

(In formulas (1) to (4), R ¹¹ represents a group selected from the group consisting of hydrogen atom, fluorine atom, hydroxyl group, alkyl group with 1 to 4 carbon atoms, and halogenated alkyl group with 1 to 4 carbon atoms. 1 type; in formula (4), Q represents 9,9'-fluorenylidene, or is selected from the formula -C ₆ H ₄ -, -CONH-C ₆ H ₄ -NHCO-, -NHCO-C ₆ H ₄ -CONH-, -OC ₆ H ₄ -CO-C ₆ H ₄ -O-, -OCO-C ₆ H ₄ -COO-, -OCO-C ₆ H ₄ -C ₆ H ₄ -COO-, - OCO-, -O-, -S-, -CO-, -CONH-, -SO ₂ -, -C(CF ₃ ) ₂ -, -C(CH ₃ ) ₂ -, -CH ₂ -, -OC ₆ H ₄ -C(CH ₃ ) ₂ -C ₆ H ₄ -O-, -OC ₆ H ₄ -C(CF ₃ ) ₂ -C ₆ H ₄ -O-, -OC ₆ H ₄ -SO ₂ -C ₆ H ₄ -O-, -C(CH ₃ ) ₂ -C ₆ H ₄ -C(CH ₃ ) ₂ -, -OC ₁₀ H ₆ -O-, -OC ₆ H ₄ -C ₆ H ₄ -O-, and one of the groups represented by -OC ₆ H ₄ -O-; in the example of Q, -C ₆ H ₄ - is phenylene, preferably m-phenylene and para-phenylene , more preferably p-phenylene; and, -C ₁₀ H ₆ - is naphthalenediyl, preferably 1,2-naphthalenediyl, 1,4-naphthalenediyl, 2,3-naphthalenediyl base, 2,6-naphthalenediyl, and 2,7-naphthalenediyl, more preferably 1,4-naphthalenediyl, and 2,6-naphthalenediyl. As one of the formulas (1) to (4) R ¹¹ is more preferably a hydrogen atom, a hydroxyl group, a fluorine atom, a methyl group, an ethyl group, or a trifluoromethyl group, especially preferably a hydrogen atom, a hydroxyl group, or a trifluoromethyl group, in terms of the heat resistance of the formed cured product. Fluoromethyl group. As Q in the formula (4), in terms of the heat resistance of the cured product formed, it is preferably 9,9'-fenylene, -OC ₆ H ₄ -O-, -C (CF ₃ ) ₂ -, -O-, -C(CH ₃ ) ₂ -, -CH ₂ -, or -OC ₆ H ₄ -C(CH ₃ ) ₂ -C ₆ H ₄ -O-, -CONH- , especially preferably -OC ₆ H ₄ -O-, -C(CF ₃ ) ₂ - or -O-. In the case of using an aromatic diamine as the diamine compound represented by the formula (a3-1), for example The following aromatic diamines can be suitably used. That is, examples of aromatic diamines include: p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 4,4'-diamine Biphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 3,3'-diaminodiphenyl, 4,4'-diaminodiphenyl Diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl Base ether, 3,3'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1, 3-bis(3-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]pyridine, Bis[4-(3-aminophenoxy)phenyl]pyridine, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4 -Aminophenoxy) phenyl] hexafluoropropane, 9,9-bis(4-aminophenyl) fluorene, 9,9-bis(4-amino-3-methylphenyl) fluorine, and 4,4'-[1,4-Phenylbis(1-methylethane-1,1-diyl)]diphenylamine, etc. Among these, p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, and 4,4'-diaminodiphenyl ether are preferred in terms of price and availability. . Also, as B, a group containing a silicon atom may be used, and the silicon atom may have a chain aliphatic group and/or an aromatic ring. As such a silicon atom-containing group, typically, the groups shown below can be used. [chemical 8]

Also, as B, a group represented by the following formula (Si-1) can also be preferably used from the viewpoint of further improving the mechanical properties of the obtained cured product. [chemical 9]

(In formula (Si-1), R ¹² and R ¹³ are each independently a single bond or a methylene group, an alkylene group with 2 to 20 carbon atoms, a cycloalkylene group with 3 to 20 carbon atoms, or a carbon atom An aryl group with a number of 6 to 20, etc. R ¹⁴ , R ¹⁵ , R ¹⁶ , and R ¹⁷ are each independently an alkyl group with 1 to 20 carbon atoms, a cycloalkyl group with 3 to 20 carbon atoms, or a cycloalkyl group with 6 carbon atoms An aryl group with ∼20 carbon atoms, a group containing an amino group with 20 or less carbon atoms, a group represented by -OR ¹⁸ (R ¹⁸ is a hydrocarbon group with 1 to 20 carbon atoms), a group with 2 to 20 carbon atoms containing one The organic group of the above epoxy group, l is an integer of 3 to 50) As the alkylene group with 2 to 20 carbon atoms in R ¹² and R ¹³ in the formula (Si-1), the heat resistance and residual stress From a viewpoint, it is preferably an alkylene group having 2 to 10 carbon atoms, and examples thereof include dimethylene, trimethylene, tetramethylene, pentamethylene, and hexamethylene. The cycloalkylene group having 3 to 20 carbon atoms in R ¹² and R ¹³ in the formula (Si-1) is preferably a cycloalkylene group having 3 to 10 carbon atoms from the viewpoint of heat resistance and residual stress. Cycloalkyl groups include cyclobutylene, cyclopentylene, cyclohexylene, cycloheptylene and the like. As the arylylene group with 6 to 20 carbon atoms in R ¹² and R ¹³ in the formula (Si-1), it is preferably an aromatic group with 6 to 20 carbon atoms from the viewpoint of heat resistance and residual stress. As a group, a phenylene group, a naphthylene group, etc. are mentioned. The alkyl group having 1 to 20 carbon atoms in R ¹⁴ , R ¹⁵ , R ¹⁶ , and R ¹⁷ in formula (Si-1) is preferably 1 carbon atom in terms of heat resistance and residual stress. The alkyl group of -10 specifically includes a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a pentyl group, and a hexyl group. As a cycloalkyl group having 3 to 20 carbon atoms among R ¹³ , R ¹⁵ , R ¹⁶ , and R ¹⁷ in formula (Si-1), from the viewpoint of heat resistance and residual stress, the number of carbon atoms is preferably As a cycloalkyl group of 3-10, a cyclopentyl group, a cyclohexyl group, etc. are mentioned specifically,. As the aryl group having 6 to 20 carbon atoms among R ¹⁴ , R ¹⁵ , R ¹⁶ , and R ¹⁷ in formula (Si-1), preferably having 6 carbon atoms in terms of heat resistance and residual stress The aryl group of -12 specifically includes phenyl, tolyl, naphthyl and the like. In formula (Si-1), R ¹⁴ , R ¹⁵ , R ¹⁶ , and R ¹⁷ have 20 or less carbon atoms containing amino groups, including amino groups, substituted amino groups (for example, bis( Trialkylsilyl) Amino) etc. Examples of the group represented by -OR ¹⁸ in R ¹⁴ , R ¹⁵ , R ¹⁶ , and R ¹⁷ in formula (Si-1) include: methoxy, ethoxy, propoxy, isopropoxy, Butoxy, phenoxy, tolyloxy, naphthyloxy, propyleneoxy (for example, allyloxy), cyclohexyloxy, and the like. Among them, R ¹⁴ , R ¹⁵ , R ¹⁶ , and R ¹⁷ are preferably methyl, ethyl, propyl, or phenyl. The group represented by the formula (Si-1) can be introduced by allowing a silicon-containing compound having amino groups at both ends to act on an acid anhydride. Specific examples of such silicon-containing compounds include two-terminal amino-modified methylphenylpolysiloxane (for example, X-22-1660B-3 (number average molecular weight: about 4,400) manufactured by Shin-Etsu Chemical Co., Ltd.) and X- 22-9409 (the number average molecular weight is about 1,300)), two-terminal amino-modified dimethylpolysiloxane (for example, X-22-161A manufactured by Shin-Etsu Chemical Co., Ltd. (the number average molecular weight is about 1,600), X-22- 161B (number average molecular weight is about 3,000) and KF8012 (number average molecular weight is about 4,400); BY16-835U manufactured by Dow Corning Toray (number average molecular weight is about 900); and Silaplane FM3311 (number average molecular weight is 1000) manufactured by JNC left and right)) etc. [Method for producing polyamic acid (A)] Typically, polyamic acid (A) having a structural unit represented by formula (a1) is a tetracarboxylic acid represented by the above-mentioned formula (a1-1) The polymer obtained by reacting the dianhydride and the diamine compound represented by the above formula (a3-1) in a solvent may use one or two or more kinds of diamine compound and/or tetracarboxylic dianhydride obtained polymer. For example, it may be a polymer obtained by polycondensing a diamine compound and a mixture containing two or more kinds of tetracarboxylic dianhydrides. Moreover, polyamic acid (A) can be used individually or in mixture of 2 or more types. The amount of tetracarboxylic dianhydride and diamine compound used in the synthesis of polyamic acid (A) is not particularly limited, but it is preferable to use 0.50 to 1.50 moles of diamine relative to 1 mole of tetracarboxylic dianhydride The compound is more preferably used at 0.60 to 1.30 mol, and particularly preferably used at 0.70 to 1.20 mol. Moreover, the weight average molecular weight of the obtained polyamic acid (A) should just be set suitably according to the use, For example, it is 5000 or more, Preferably it is 7500 or more, More preferably, it is 10000 or more. On the other hand, the weight average molecular weight of the obtained polyamic acid (A) is, for example, 100,000 or less, preferably 80,000 or less, more preferably 75,000 or less. This weight average molecular weight can be made into the said value by adjusting reaction conditions, such as the compounding quantity of tetracarboxylic dianhydride and a diamine compound, a solvent, or reaction temperature. The reaction of tetracarboxylic dianhydride and diamine compound is usually carried out in an organic solvent. For the organic solvent used in the reaction of tetracarboxylic dianhydride and diamine compound, as long as it is an organic solvent that can dissolve tetracarboxylic dianhydride and diamine compound and does not react with tetracarboxylic dianhydride and diamine compound. Yes, there are no special restrictions. An organic solvent may be used individually or in mixture of 2 or more types. Examples of organic solvents used in the reaction between tetracarboxylic dianhydride and diamine compounds include: N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-di Ethylacetamide, N,N-dimethylformamide, N,N-diethylformamide, N-methylcaprolactam, and N,N,N',N'-tetramethylformamide Nitrogen-containing polar solvents such as urea; dimethylsulfoxide; acetonitrile; ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dioxane, and tetrahydrofuran. Among these organic solvents, N-methyl-2-pyrrolidone, N,N-dimethicone are preferred in terms of the solubility of polyamide acid (A) and polyimide resin produced. Methylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, N,N-diethylformamide, N-methylcaprolactam, and N ,N,N',N'-tetramethylurea and other nitrogen-containing polar solvents. The temperature at the time of making a tetracarboxylic dianhydride and a diamine compound react will not be specifically limited if reaction can progress favorably. Typically, the reaction temperature between the tetracarboxylic dianhydride and the diamine compound is preferably from -5 to 150°C, more preferably from 0 to 120°C, and especially preferably from 0 to 70°C. The time to react the tetracarboxylic dianhydride and the diamine compound varies depending on the reaction temperature, but typically, it is preferably from 1 to 50 hours, more preferably from 2 to 40 hours, and especially preferably from 5 to 30 hours. A solution containing polyamide acid (A) can be obtained by the method described above. The method for preparing the resin composition of the first aspect is not particularly limited, and it is preferable to mix carbonyl oxides selected from the group consisting of -CO-O- bonds in the molecule into the obtained solution containing polyamic acid (A). One or more methods in the group consisting of a base compound (B1) and a basic nitrogen-containing compound (B2) without a -CO-O- bond in the molecule. The solution containing polyamic acid (A) as mentioned above can be directly used in the preparation of the resin composition, and the paste or solid of polyamic acid can also be used in the preparation of the resin composition. The paste or solid system It is obtained by removing at least a part of the solvent from a solution of polyamic acid (A) under reduced pressure at such a low temperature that the conversion of polyamic acid to polyimide resin does not occur. <Carbonyloxy compound (B1) and basic nitrogen-containing compound (B2)> The resin composition contains a carbonyloxy compound (B1) having a -CO-O- bond in the molecule, and a carbonyloxy compound (B1) not having a -CO- in the molecule. One or more types of the group consisting of basic nitrogen-containing compounds (B2) with O-bonds. The carbonyloxy compound (B1) and the basic nitrogen-containing compound (B2) are components for promoting the production of polyimide from polyamic acid (A). Therefore, if the resin composition of the first aspect is used, the polyamic acid (A) is converted into polyimide at an appropriate speed, and a cured product with stable shape can be easily obtained. Although only using any one of the carbonyloxy compound (B1) and the basic nitrogen-containing compound (B2) also obtains the effect of promoting the generation of polyimide, it is relatively inferior in terms of the curability of the resin composition. Preferably, the carbonyloxy compound (B1) and the basic nitrogen-containing compound (B2) are combined and formulated into the resin composition. Hereinafter, the carbonyloxy compound (B1) and the basic nitrogen-containing compound (B2) will be described respectively. [Carbonyloxy compound (B1)] The carbonyloxy compound is not particularly limited as long as it has a -CO-O- bond in the molecule. The carbonyloxy compound (B1) facilitates the hardening of the resin composition by promoting the ring closure by dehydration in the polyamic acid (A). As a carbonyloxy compound (B1), a carboxylic acid, a carboxylic acid ester, a carboxylic anhydride, a carbonate etc. are mentioned, for example. Carbonyloxy compound (B1) can also be used in combination of 2 or more types. (Carboxylic acid) The carboxylic acid may be an aliphatic carboxylic acid or an aromatic carboxylic acid. In addition, the carboxylic acid may be a monovalent carboxylic acid having one carboxyl group, or may be a polyvalent carboxylic acid having two or more carboxyl groups. Moreover, although the number of carbon atoms of a carboxylic acid is not specifically limited, Preferably it is 1-50, More preferably, it is 1-30. Preferable specific examples of carboxylic acids include aliphatic acids such as formic acid, acetic acid, propionic acid, butyric acid, valeric acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, capric acid, lactic acid, acrylic acid, and methacrylic acid. Monocarboxylic acids; aliphatic polycarboxylic acids such as oxalic acid, maleic acid, adipic acid, sebacic acid, azelaic acid, fumaric acid, and itaconic acid; benzoic acid, salicylic acid, p-hydroxy Benzoic acid, m-hydroxybenzoic acid, o-chlorobenzoic acid, p-chlorobenzoic acid, m-chlorobenzoic acid, o-toluic acid, p-toluic acid, m-toluic acid, terephthalic acid, isophthalic acid , phthalic acid, 2,6-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 4,4'-dicarboxybiphenyl, 4,4'-dicarboxydiphenyl ether, and trimellitate Aromatic carboxylic acids such as formic acid. Also, as the carboxylic acid, a compound having an aromatic group and a carboxyl group bonded to an alkylene group is also preferable. Specific examples of such compounds include phenylacetic acid, 3-phenylpropionic acid, 4-phenylbutyric acid, and the like. Moreover, in this embodiment, the compound represented by following formula (b1-1) is mentioned as a carboxylic acid preferably used, for example. [chemical 10]

(In formula (b1-1), R ^b0 , R ^b1 and R ^b2 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a mercapto group, a sulfide group (sulfide group), a silyl group, a silanol group, a nitro group, a nitroso group group, sulfino group, sulfo group, sulfonato group, phosphino group, phosphinyl group, phosphono group, phosphonato group group), or an organic group, either of R ^b0 and R ^b1 is an aromatic group that may have a substituent, or an alkyl group) As the organic group in the formula (b1-1), examples include: an alkyl group, a chain Alkenyl, cycloalkyl, cycloalkenyl, aryl, aralkyl, etc. The organic group may contain bonds or substituents other than hydrocarbon groups such as heteroatoms in the organic group. Moreover, this organic group may be any of linear, branched, and cyclic. This organic group is usually monovalent, but may be a divalent or higher organic group when forming a ring structure. The bond contained in the organic group is not particularly limited as long as it does not impair the effects of the present invention, and the organic group may contain bonds containing heteroatoms such as oxygen atoms, nitrogen atoms, and silicon atoms. Specific examples of bonds containing heteroatoms include ether bonds, thioether bonds, carbonyl bonds, thiocarbonyl bonds, ester bonds, amide bonds, urethane bonds, imino bonds (-N=C (-R)-, -C(=NR)-: R represents a hydrogen atom or an organic group), a carbonate bond, a sulfonyl bond, a sulfinyl bond, an azo bond, and the like. The heteroatom-containing bond that the organic group may have is preferably an ether bond, a thioether bond, a carbonyl bond, a thiocarbonyl bond, or an ester bond from the viewpoint of the heat resistance of the compound represented by the formula (b1-1). , amide bond, urethane bond, imine bond (-N=C(-R)-, -C(=NR)-: R represents a hydrogen atom or a monovalent organic group), carbonate bond, Sulfonyl bond, sulfinyl bond. Specific examples of R ^b0 , R ^b1 , and R ^b2 include halogen atoms, hydroxyl groups, mercapto groups, thioether groups, cyano groups, isocyano groups, cyanato groups, and isocyanato groups. , thiocyanato group, isothiocyanato group, silyl group, silanol group, alkoxy group, alkoxycarbonyl group, aminoformyl group, thiocarbamoyl group, Nitro, nitroso, carboxylate group, acyl, acyloxy, sulfinic acid, sulfonic acid, phosphino, phosphinyl, phosphonic acid, alkyl ether, alkenyl Ether group, alkyl sulfide group, alkenyl sulfide group, aryl ether group, aryl sulfide group, etc. Hydrogen atoms contained in the above substituents may be substituted with hydrocarbon groups. Moreover, the hydrocarbon group contained in the said substituent may be any of linear, branched, and cyclic. In formula (b1-1), either one of R ^b0 and R ^b1 is an aromatic group or an alkyl group which may have a substituent. In formula (b1-1), when any one of R ^b0 and R ^b1 is an alkyl group, the alkyl group may be linear or branched. The number of carbon atoms in the alkyl group is preferably 1-20, more preferably 1-15, especially preferably 1-10, further preferably 1-6, most preferably 1-4. There is also a case where R ^b2 is an alkyl group, and the alkyl group in this case is preferably the same group as above. In the formula (b1-1), when any one of R ^b0 and R ^b1 is an aromatic group that may have a substituent, the type of substituent that the aromatic group may have is not hindering the object of the present invention There is no particular limitation within the scope. Suitable examples of the substituent include: halogen atom, hydroxyl group, mercapto group, thioether group, silyl group, silanol group, nitro group, nitroso group, sulfonic acid group, phosphino group, phosphinyl group, phosphonic acid group , or organic base. In formula (b1-1), when any one of R ^b0 and R ^b1 is an aromatic group which may have a substituent, the aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group, An aromatic hydrocarbon group is preferred. Suitable examples of the aromatic group include phenyl, naphthyl, biphenyl, anthracenyl, and phenanthrenyl. Among these aromatic groups, phenyl is preferred. There is also a case where R ^b2 is an aromatic group which may have a substituent, and the aromatic group which may have a substituent in this case is preferably the same group as above. Specific examples of the substituent that the aromatic group may have are the same as the specific examples of R ^b0 , R ^b1 and R ^b2 . Among the compounds represented by the formula (b1-1), preferred compounds include compounds represented by the following formula (b1-2). [chemical 11]

(In the formula (b1-2), R ^b1 and R ^b2 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfinic acid group , sulfo group, sulfonic acid group, phosphino group, phosphinyl group, phosphono group, phosphonic acid group, or organic group; R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 each independently represent a hydrogen atom, a halogen Atom, hydroxyl, mercapto, thioether, silane, silanol, nitro, nitroso, sulfinate, sulfo, sulfonate, phosphino, phosphinyl, phosphono, phosphonate , amine group, ammonium group, or organic group; two or more of R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 can also be bonded to form a ring structure, R ^b3 , R ^b4 , R ^b5 , R ^b6 and R ^b7 may also contain a heteroatom bond) The organic groups in R ^b1 and R ^b2 are the same as those described for formula (b1-1). Among the above, R ^b1 and R ^b2 in the formula (b1-2) are each independently preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 4 to 13 carbon atoms, a carbon Cycloalkenyl group with 4 to 13 atoms, aryloxyalkyl group with 7 to 16 carbon atoms, aralkyl group with 7 to 20 carbon atoms, alkyl group with 2 to 11 carbon atoms having a cyano group, Alkyl group with 1 to 10 carbon atoms, alkoxy group with 1 to 10 carbon atoms, amido group with 2 to 11 carbon atoms, alkylthio group with 1 to 10 carbon atoms, 1 to 10 carbon atoms An acyl group of ~10, an aryl group with 6 to 20 carbon atoms, an aryl group with 6 to 20 carbon atoms substituted with an electron-donating group and/or an electron-withdrawing group, an electron-donating group and/or an electron-withdrawing group Electronic benzyl, cyano, methylthio. More preferably, both R ^b1 and R ^b2 are hydrogen atoms, or R ^b1 is a methyl group, and R ^b2 is a hydrogen atom. Examples of the organic group in R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 include those exemplified for R ^b1 and R ^b2 . The organic group may contain a bond or a substituent other than a hydrocarbon group such as a heteroatom in the same manner as R ^b1 and R ^b2 . Moreover, this organic group may be any of linear, branched, and cyclic. Regarding R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 , two or more of them may be bonded to form a ring structure, and bonds of heteroatoms may be included. As a ring structure, a heterocycloalkyl group, a heteroaryl group, etc. are mentioned, and a condensed ring may be sufficient. For example, two or more of R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 may be bonded, sharing the benzene ring to which R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 are bonded. atoms to form condensed rings such as naphthalene, anthracene, phenanthrene, indene, etc. Among the above, R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 are each independently preferably a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a cycloalkyl group having 4 to 13 carbon atoms. , cycloalkenyl group with 4 to 13 carbon atoms, aryloxyalkyl group with 7 to 16 carbon atoms, aralkyl group with 7 to 20 carbon atoms, and alkyl group with 2 to 11 carbon atoms having a cyano group , Alkyl group with 1 to 10 carbon atoms, alkoxy group with 1 to 10 carbon atoms, amido group with 2 to 11 carbon atoms, alkylthio group with 1 to 10 carbon atoms, carbon atom Acyl group with 1 to 10 carbon atoms, ester group with 2 to 11 carbon atoms, aryl group with 6 to 20 carbon atoms, aromatic group with 6 to 20 carbon atoms substituted with electron-donating and/or electron-withdrawing groups group, benzyl group, cyano group, methylthio group, nitro group substituted with electron-donating group and/or electron-withdrawing group. Also, as R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 , it is also preferable to bond two or more of them, and to share R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 Atoms of bonded benzene rings form condensed rings such as naphthalene, anthracene, phenanthrene, indene, etc. Among the compounds represented by the above formula (b1-2), compounds represented by the following formula (b1-3) are preferred. [chemical 12]

(In formula (b1-3), R ^b1 to R ^b6 are the same as formula (b1-2); R ^b8 represents a hydrogen atom or an organic group; R ^b3 and R ^b4 do not become hydroxyl groups; R ^b3 , R ^b4 , R ^b5 , and two or more of R ^b6 may be bonded to form a ring structure, and may also contain a bond of a heteroatom) The compound represented by the formula (b1-3) has a substituent -OR ^b8 , so it is easy to uniformly disperse or Dissolved in the resin composition. In formula (b1-3), R ^b8 is a hydrogen atom or an organic group. When R ^b8 is an organic group, examples of the organic group include groups exemplified for R ^b1 and R ^b2 . The organic group may also contain heteroatoms in the organic group. Moreover, this organic group may be any of linear, branched, and cyclic. R ^b8 is preferably a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, more preferably a methyl group. Specific examples of particularly preferable compounds among the compounds represented by the formula (b1-1) are shown below. [chemical 13]

(Carboxylate) Carboxylate is not particularly limited as long as it is a compound having an ester bond. A carboxylate may also have an aromatic group. As carboxylic acid esters, for example, the following esters of the above-mentioned carboxylic acids can be cited: C ₁ -C ₁₀ alkyl esters, C ₃ -C ₁₀ cycloalkyl esters, phenyl esters, C ₆ -C ₁₀ alkylphenyl esters , C ₇ -C ₁₀ alkoxyphenyl esters, naphthyl esters, C ₇ -C ₁₀ aralkyl esters, etc. When the carboxylate is an ester of polycarboxylic acid, the carboxylate may have both an ester bond and a carboxyl group. For example, monomethyl terephthalate and the like are also carboxylic acid esters. Preferred specific examples of carboxylic acid esters include: methyl formate, ethyl formate, n-propyl formate, isopropyl formate, n-butyl formate, isobutyl formate, second butyl formate, third formic acid Butyl, n-pentyl formate, n-hexyl formate, n-heptyl formate, n-octyl formate, cyclopropyl formate, cyclobutyl formate, cyclopentyl formate, cyclohexyl formate, cycloheptyl formate, cyclooctyl formate ester, phenyl formate, o-cresyl formate, m-cresyl formate, p-cresyl formate, α-naphthyl formate, β-naphthyl formate, benzyl formate, and phenylethyl formate and other formate esters; acetic acid Methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, second-butyl acetate, third-butyl acetate, n-pentyl acetate, n-hexyl acetate, n-acetate Heptyl acetate, n-octyl acetate, cyclopropyl acetate, cyclobutyl acetate, cyclopentyl acetate, cyclohexyl acetate, cycloheptyl acetate, cyclooctyl acetate, phenyl acetate, o-cresyl acetate, m-toluene acetate Acetate esters, p-cresyl acetate, α-naphthyl acetate, β-naphthyl acetate, benzyl acetate, and phenethyl acetate; methyl propionate, ethyl propionate, n-propyl propionate , isopropyl propionate, n-butyl propionate, isobutyl propionate, second butyl propionate, third butyl propionate, n-pentyl propionate, n-hexyl propionate, n-heptyl propionate, N-octyl propionate, cyclopropyl propionate, cyclobutyl propionate, cyclopentyl propionate, cyclohexyl propionate, cycloheptyl propionate, cyclooctyl propionate, phenyl propionate, o-propionate Cresyl, m-cresyl propionate, p-cresyl propionate, α-naphthyl propionate, β-naphthyl propionate, benzyl propionate, and propionate such as phenylethyl propionate; methyl acrylate , ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, second butyl acrylate, third butyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-heptyl acrylate , n-octyl acrylate, cyclopropyl acrylate, cyclobutyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, cycloheptyl acrylate, cyclooctyl acrylate, phenyl acrylate, o-cresyl acrylate, m-cresyl acrylate, Acrylates such as p-cresyl acrylate, α-naphthyl acrylate, β-naphthyl acrylate, benzyl acrylate, and phenylethyl acrylate; methyl methacrylate, ethyl methacrylate, n-propyl methacrylate , isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, second butyl methacrylate, third butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate , n-heptyl methacrylate, n-octyl methacrylate, cyclopropyl methacrylate, cyclobutyl methacrylate, cyclopentyl methacrylate, cyclohexyl methacrylate, cycloheptyl methacrylate, Cyclooctyl methacrylate, phenyl methacrylate, o-cresyl methacrylate, m-cresyl methacrylate, p-cresyl methacrylate, α-naphthyl methacrylate, β-naphthyl methacrylate methacrylates such as esters, benzyl methacrylate, and phenylethyl methacrylate; methyl benzoate, ethyl benzoate, n-propyl benzoate, isopropyl benzoate, n-butyl benzoate, benzene Isobutyl formate, Second-butyl benzoate, Tertiary-butyl benzoate, n-pentyl benzoate, n-hexyl benzoate, n-heptyl benzoate, n-octyl benzoate, cyclopropyl benzoate, benzoic acid Cyclobutyl benzoate, cyclopentyl benzoate, cyclohexyl benzoate, cycloheptyl benzoate, cyclooctyl benzoate, phenyl benzoate, o-cresyl benzoate, m-cresyl benzoate, p-cresyl benzoate , α-naphthyl benzoate, β-naphthyl benzoate, benzyl benzoate, and phenylethyl benzoate and other benzoate esters; dimethyl terephthalate, diethyl terephthalate, Di-n-propyl terephthalate, di-isopropyl terephthalate, di-n-butyl terephthalate, di-isobutyl terephthalate, di-second-butyl terephthalate, terephthalic acid Di-tert-butyl ester, di-n-pentyl terephthalate, di-n-hexyl terephthalate, di-n-heptyl terephthalate, di-n-octyl terephthalate, dicyclopropyl terephthalate, Dicyclobutyl terephthalate, dicyclopentyl terephthalate, dicyclohexyl terephthalate, dicyclohexyl terephthalate, dicycloctyl terephthalate, dicyclohexyl terephthalate Phenyl esters, di-o-cresyl terephthalate, di-m-cresyl terephthalate, di-p-cresyl terephthalate, bis(α-naphthyl) terephthalate, bis(β) terephthalate Terephthalic acid diesters such as -naphthyl) ester, dibenzyl terephthalate, and diphenylethyl terephthalate; ethylene glycol monoacetate, ethylene glycol monopropionate, ethylene glycol Monobutyrate, Ethylene Glycol Monovalerate, Ethylene Glycol Monobenzoate, Ethylene Glycol Diacetate, Ethylene Glycol Dipropionate, Ethylene Glycol Dibutyrate, Ethylene Glycol Di Ethylene glycol esters such as valerate and ethylene glycol dibenzoate; Diethylene glycol monoacetate, diethylene glycol monopropionate, diethylene glycol monobutyrate, diethylene glycol Monovalerate, Diethylene Glycol Monobenzoate, Diethylene Glycol Diacetate, Diethylene Glycol Dipropionate, Diethylene Glycol Dibutyrate, Diethylene Glycol Divalerate , and diethylene glycol dibenzoate and other diethylene glycol esters; propylene glycol monoacetate, propylene glycol monopropionate, propylene glycol monobutyrate, propylene glycol monovalerate, propylene glycol monobenzoate, propylene glycol Propylene Glycol Esters such as Diacetate, Propylene Glycol Dipropionate, Propylene Glycol Dibutyrate, Propylene Glycol Divalerate, and Propylene Glycol Dibenzoate; Dipropylene Glycol Monoacetate, Dipropylene Glycol Monopropionate, Dipropylene Glycol Monobutyrate, Dipropylene Glycol Monovalerate, Dipropylene Glycol Monobenzoate, Dipropylene Glycol Diacetate, Dipropylene Glycol Dipropionate, Dipropylene Glycol Dibutyrate, Dipropylene Glycol Divalerate, and Dipropylene Glycol Divalerate Dipropylene glycol esters such as propylene glycol dibenzoate. Also, as the carboxylic acid ester, the following esters of the carboxylic acid represented by the above-mentioned formula (b1-1) are also preferred: methyl ester, ethyl ester, n-propyl ester, isopropyl ester, n-butyl ester, isobutyl ester , second butyl ester, third butyl ester, n-pentyl ester, n-hexyl ester, n-heptyl ester, n-octyl ester, cyclopropyl ester, cyclobutyl ester, cyclopentyl ester, cyclohexyl ester, cycloheptyl ester, cyclooctyl ester, Phenyl esters, o-cresyl esters, m-cresyl esters, p-cresyl esters, α-naphthyl esters, β-naphthyl esters, benzyl esters, and phenethyl esters. (Carboxylic acid anhydride) The carboxylic acid anhydride will not be specifically limited if it is a compound which has a carboxylic acid anhydride group (-CO-O-CO-). Suitable examples of carboxylic anhydrides include acetic anhydride, propionic anhydride, butyric anhydride, benzoic anhydride, phthalic anhydride, naphthalene dicarboxylic anhydride, succinic anhydride, chlorobridge anhydride, nadic anhydride (himic anhydride), cisanhydride Butenedioic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, diphenyl Methanone tetracarboxylic anhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, and 5-(2,5-oxotetrahydrofuranyl)-3-methyl-3-cyclohexene-1,2 -Dicarboxylic acid anhydride, styrene-maleic anhydride copolymer, etc. (Carbonate) Carbonate will not be specifically limited if it is a compound which has a carbonate bond (-O-CO-O-). The carbonate may be a chain carbonate such as dimethyl carbonate or a cyclic carbonate such as ethylene carbonate. Preferred specific examples of carbonate compounds include dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate. wait. Among the carbonyloxy compounds (B1) described above, a compound represented by the following formula (b1) is particularly preferable. [chemical 14]

(In formula (b1), R ^b0 is an alkyl group or an aromatic group that may have a substituent, and R ^b9 is a hydrogen atom or an alkyl group.) When R ^b9 is an alkyl group, the alkyl group and the above formula The alkyl groups of R ^b0 in (b1-1) are the same. Moreover, in the present embodiment, R ^b9 is particularly preferably a hydrogen atom from the viewpoint of being able to convert polyamic acid (A) into polyimide at an appropriate rate. [Basic Nitrogen-Containing Compound (B2)] The basic nitrogen-containing compound (B2) is not particularly limited as long as it contains a nitrogen atom and exhibits basicity in Brenest's definition. Examples of the basic nitrogen-containing compound (B2) include ammonia, methylamine, ethylamine, n-propylamine, isopropylamine, isobutylamine, n-butylamine, n-pentylamine, n-hexylamine, dimethylamine, and diethylamine. , di-n-propylamine, diisopropylamine, diisobutylamine, di-n-butylamine, di-n-pentylamine, di-n-hexylamine, trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, triisobutylamine, tri-n- Butylamine, tri-n-pentylamine, tri-n-hexylamine, aniline, o-toluidine, m-toluidine, p-toluidine, α-naphthylamine, β-naphthylamine, and o-phenylenediamine, m-phenylenediamine, p-phenylenediamine Acyclic amines such as amines. Also, guanidine, aminopyridine, aminoalkylpyridine, aminopyrrolidine, indazole, imidazole, pyrazole, pyrimidine, pyrimidine, purine, imidazoline, pyrazoline, piperazine, aminomorpholine, and Aminoalkylmorpholine and the like are also preferable as the basic nitrogen-containing compound (B2). The above compounds may also have a substituent, and examples of preferred substituents include amino, aminoalkyl, alkylamino, aminoaryl, arylamino, alkyl, alkoxy, acyl, Acyloxy, aryl, aryloxy, nitro, hydroxyl, cyano, etc. Examples of particularly preferred organic basic compounds (B2) include: guanidine, 1,1-dimethylguanidine, 1,1,3,3-tetramethylguanidine, imidazole, 2-methylimidazole, 4-formazolidine imidazole, N-methylimidazole, 2-phenylimidazole, 4,5-diphenylimidazole, 2,4,5-triphenylimidazole, 2-aminopyridine, 3-aminopyridine, 4-amine Basepyridine, 2-dimethylaminopyridine, 4-dimethylaminopyridine, 2-diethylaminopyridine, 2-(aminomethyl)pyridine, 2-amino-3-methylpyridine , 2-amino-4-picoline, 2-amino-5-picoline, 2-amino-6-picoline, 3-aminoethylpyridine, 4-aminoethylpyridine, 3-aminopyrrolidine, piperidine, N-(2-aminoethyl)piperidine, N-(2-aminoethyl)piperidine, 4-amino-2,2,6,6-tetra Methylpiperidine, 4-piperidinylpiperidine, 2-iminopiperidine, 1-(2-aminoethyl)pyrrolidine, pyrazole, 3-amino-5-methylpyrazole, 5 -Amino-3-methyl-1-p-tolylpyrazole, pyridine, 2-(aminomethyl)-5-methylpyrazole, pyrimidine, 2,4-diaminopyrimidine, 4,6 -Dihydroxypyrimidine, 2-pyrazoline, 3-pyrazoline, N-aminomorpholine, N-(2-aminoethyl)morpholine, and 1,8-diazabicyclo[5.4.0 ]-7-undecene, etc. As mentioned above, the basic nitrogen-containing compound (B2) has been described, and the basic nitrogen-containing compound (B2) preferably contains imidazole in terms of the effect of accelerating the hardening of the polyamic acid (A). Ring imidazole compound. Such an imidazole compound is typically represented by the following formula (b2-1). [chemical 15]

(In the formula (b2-1), R ^b10 , R ^b11 , and R ^b12 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a mercapto group, a thioether group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfo acid group, phosphine group, phosphinyl group, phosphonic acid group, or organic group) As the organic group in R ^b10 , R ^b11 , and R ^b12 in formula (b2-1), examples include: alkyl, alkenyl, Cycloalkyl, cycloalkenyl, aryl, aralkyl, etc. The organic group may contain bonds or substituents other than hydrocarbon groups such as heteroatoms in the organic group. Moreover, this organic group may be any of linear, branched, and cyclic. This organic group is usually monovalent, and may be a divalent or higher organic group when forming a cyclic structure or the like. The organic groups in R ^b10 , R ^b11 , and R ^b12 in formula (b2-1) are the same as those in formula (b1-1). R ^b10 , R ^b11 , and R ^b12 are preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, and a halogen atom, more preferably a hydrogen atom. The total amount of the content of the carbonyloxy compound (B1) and the content of the basic nitrogen-containing compound (B2) in the resin composition is not particularly limited within the range that does not hinder the purpose of the present invention, relative to 100 parts by mass of polyamide Amino acid (A), the above-mentioned total amount is preferably 0.01-30 parts by mass, more preferably 0.05-25 parts by mass, especially preferably 0.2-20 parts by mass. Also, when the carbonyloxy compound (B1) and the basic nitrogen-containing compound (B2) are used together, the mass W _B1 of the carbonyloxy compound (B1) and the mass W B2 of the basic nitrogen-containing compound ( _B2 ) The ratio W _B1 /W _B2 is preferably 1/99 to 99/1, more preferably 5/95 to 95/5, particularly preferably 15/85 to 85/15. <Solvent (S)> It is preferable that a resin composition contains a solvent (S) from the point of applicability. The resin composition may be a paste containing solids or a solution, preferably a solution. A solvent (S) can be used individually or in mixture of 2 or more types. The kind of solvent (S) is not specifically limited in the range which does not interfere with the objective of this invention. A suitable example of the solvent (S) is the same as the example of the solvent used for the reaction of the above-mentioned tetracarboxylic dianhydride and a diamine compound. In addition, the solvent (S) may contain alcohol-based solvents such as polyethylene glycol, ethylene glycol, diethylene glycol, propylene glycol, and dipropylene glycol. When the solvent (S) contains an alcohol-based solvent, it is easy to form a cured product excellent in heat resistance. Moreover, the solvent (S) containing the compound (S1) represented by following formula (5) can also be used. [chemical 16]

(In the formula (5), R ^S1 and R ^S2 are each independently an alkyl group with 1 to 3 carbon atoms, and R ^S3 is a group represented by the following formula (5-1) or the following formula (5-2), 17]

In formula (5-1), R ^S4 is a hydrogen atom or a hydroxyl group, R ^S5 and R ^S6 are each independently an alkyl group with 1 to 3 carbon atoms; in formula (5-2), R ^S7 and R ^S8 are each independently A hydrogen atom, or an alkyl group having 1 to 3 carbon atoms) In the compound (S1) represented by the formula (5), specific examples of the case where R ^S3 is a group represented by the formula (5-1) include: N,N,2-trimethylpropionamide, N-ethyl-N,2-dimethylpropionamide, N,N-diethyl-2-methylpropionamide, N,N,2 -Trimethyl-2-hydroxypropionamide, N-ethyl-N,2-dimethyl-2-hydroxypropionamide, and N,N-diethyl-2-hydroxy-2-methylpropane Amide, etc. In the compound (S1) represented by the formula (5), specific examples of the case where R ^S3 is a group represented by the formula (5-2) include: N,N,N',N'-tetramethylurea , N,N,N',N'-tetraethylurea, etc. Among the above-mentioned examples of the compound (S1), N,N,2-trimethylacrylamide and N,N,N',N'-tetramethylurea are more preferable examples. When the resin composition contains a solvent (S), the content of the compound (S1) in the solvent (S) is not particularly limited within the range that does not interfere with the object of the present invention. The mass ratio of the compound (S1) to the solvent is typically preferably at least 70% by mass, more preferably at least 80% by mass, particularly preferably at least 90% by mass, based on the total amount of the solvent (S), The best is 100% by mass. Examples of organic solvents that can be used together with compound (S1) include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, Nitrogen-containing polar solvents such as hexamethylphosphoramide and 1,3-dimethyl-2-imidazolinone; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and isophorone cyclic ethers such as dioxane and tetrahydrofuran; aromatic hydrocarbons such as toluene and xylene; Content of the solvent (S) in a resin composition is not specifically limited in the range which does not interfere with the objective of this invention. The content of the solvent (S) in the resin composition can be appropriately adjusted according to the solid content in the resin composition. The solid content in the resin composition is preferably from 5 to 70% by mass, more preferably from 10 to 60% by mass. <Other components> The resin composition may contain other components other than the above-mentioned components within the range which does not interfere with the objective of this invention. Examples of other components include surfactants, plasticizers, viscosity modifiers, defoamers, and colorants. ≪Method for producing a cured product≫ The method for producing a cured product according to the second aspect includes the following steps: a coating film forming step of coating the resin composition of the first aspect on a substrate to form a coating film; and a heating step, The coating film is heated at 70-550°C. In this method, since a coating film is formed using the resin composition of the first aspect, a cured product containing polyimide is stably produced. As a result, a hardened product having a smooth surface with less unevenness, warpage, or cracks and excellent appearance can be obtained. <Coating film formation process> In a formation process, the resin composition of 1st aspect is apply|coated on the surface of a base material, and a coating film is formed. As a coating method, a dip coating method, a spray method, a bar coating method, a roll coating method, a spin coating method, a curtain coating method, etc. are mentioned, for example. After coating, the coating film may be placed in a reduced-pressure atmosphere for the purpose of promoting degassing and removal of the solvent (S) from the coating film. The vacuum degree of the decompression atmosphere is not particularly limited, but is preferably 300 Pa or less, more preferably 150 Pa or less, and still more preferably 100 Pa or less. The thickness of the coating film is not particularly limited. Typically, the thickness of the coating film is preferably 2-100 μm, more preferably 3-50 μm. The thickness of the coating film can be appropriately controlled by adjusting the coating method, the solid content concentration or the viscosity of the resin composition. The material of the substrate is not particularly limited as long as thermal deterioration and deformation do not occur when the coating film is heated. The shape of the substrate is not particularly limited as long as it can be coated with the resin composition. Examples of the base material include electronic elements such as semiconductor elements on which electrodes to be insulated and/or wiring are formed, intermediate products such as multilayer wiring boards, and various substrates. As the preferred substrate material when the substrate is the substrate, glass; silicon; aluminum (Al); aluminum-silicon (Al-Si), aluminum-copper (Al-Cu), aluminum-silicon-copper (Al -Si-Cu) and other aluminum alloys; titanium (Ti); titanium-tungsten (Ti-W) and other titanium alloys; titanium nitride (TiN); tantalum (Ta); tantalum nitride (TaN); tungsten (W); Tungsten Nitride (WN); Copper. In addition, when the coating film is heated at low temperature, it is also possible to use a substrate with low heat resistance including resin such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT). material. <Heating step> The coating film formed in the coating film forming step is heated at 70 to 550° C. in the heating step. When heating the said coating film, heating temperature can be set to 120-500 degreeC, for example, Preferably it is 150-450 degreeC. By heating the coating film at the temperature in the above-mentioned range, thermal deterioration and thermal decomposition of the polyimide produced can be suppressed, and a cured product can be stably produced. In addition, when the coating film is heated at a high temperature, a large amount of energy may be consumed, and the time-lapse deterioration of the processing equipment at a high temperature may be accelerated, so it is also preferable to heat the coating film at a temperature lower than the above-mentioned temperature. appearance. Although the heating time also depends on the composition of the resin composition or the thickness of the coating film, etc., it can be set as follows: the lower limit is, for example, 5 minutes, preferably 10 minutes, more preferably 20 minutes; the upper limit is, for example, 4 hours , preferably 3 hours, more preferably 2.5 hours. Also, from the point of view of lowering the yellowness index of polyimide, or from the point of view of smoother conversion from polyamic acid (A) to polyimide, the atmosphere during heating (gas composition such as oxygen concentration) can be adjusted. Adjustments are made, or depressurization steps can also be combined during heating or before and after heating. [Examples] Hereinafter, examples are disclosed to describe the present invention more specifically, but the scope of the present invention is not limited to these examples. [Preparation of polyamic acid (A)] Put tetracarboxylic dianhydride and N-methyl- For 2-pyrrolidone, nitrogen gas was introduced into the flask from a nitrogen gas introduction tube to make the inside of the flask a nitrogen atmosphere. Then, the flask was immersed in an ice bath, and the N-methyl-2-pyrrolidone solution of p-phenylenediamine in an amount of 1.0 mol per tetracarboxylic dianhydride was slowly added dropwise, stirring the contents. After the dropwise addition, it was reacted at 50° C. for 20 hours to obtain a solution containing polyamic acid (A). Furthermore, the tetracarboxylic dianhydride of the structure shown below is prepared according to the methods described in Synthesis Example 1, Example 1 and Example 2 of International Publication No. 2011/099518, and the solution here is prepared It adjusted so that the solid content density|concentration of the obtained polyamic acid (A) might become 15 mass %. [chemical 18]

EXAMPLE 1-3, COMPARATIVE EXAMPLE 1 In Example 1-3, the additive shown in Table 1 was added to the solution of the polyamic acid (A) obtained in this way, and the resin composition was prepared. In Table 1, the value (mass %) shown in parentheses is the ratio of the amount of additives to the amount of polyamic acid (A). On the other hand, in Comparative Example 1, no additives were added to the solution of polyamic acid (A) obtained above. In addition, the p-methoxycinnamic acid was the one manufactured by Tokyo Chemical Industry Co., Ltd., and the imidazole was the one manufactured by Kishida Chemical Co., Ltd.. [Evaluation of Film Formability] The film formability of the various resin compositions thus obtained was evaluated in the following manner. That is, first, each resin composition was coated on a glass substrate, and the pressure was reduced to 13 Pa. After temporarily returning to normal pressure, heat at 80°C for 10 minutes under air (Air) conditions, and then heat at 360°C for 30 minutes under the condition of oxygen concentration of 100 ppm to obtain a hardened product with a film thickness of 15 μm . Regarding the cured product obtained in this way, it was observed visually whether or not a film was formed in a good shape. In addition, evaluation was performed based on the following criteria. ⊚: Confirmed visually, no roughness was observed. ◯: A substantially smooth film was formed, but warpage was observed at the edge portion. Δ: Cracks were observed in a part of the film. ×: Cracks were observed everywhere in the film. [Table 1] Table 1 Example 1 Example 2 Example 3 Comparative example 1 additive ・P-methoxycinnamic acid (3% by mass) ・Imidazole (2% by mass) · p-methoxycinnamic acid (5% by mass) ・Imidazole (5% by mass) - Film forming evaluation ◎ △ ○ x As can be seen from Table 1, by adding specific additives to polyamic acid (A), a resin composition excellent in film-forming properties and capable of stably forming a cured product containing polyimide was obtained.

Claims (9)

A resin composition comprising: a polyamic acid (A) having a structural unit represented by the following formula (a1), and a carbonyloxy compound (B1) selected from a carbonyloxy compound (B1) having a -CO-O- bond in the molecule, and One or more of the group consisting of basic nitrogen-containing compounds (B2) that do not have a -CO-O- bond in the molecule, [Chem. 1]

(In the formula (a1), A is a tetravalent polycyclic aliphatic group having 6 to 50 carbon atoms, and B is a divalent organic group). The resin composition according to claim 1, which contains a compound represented by the following formula (b1) as the carbonyloxy compound (B1), [Chem. 2]

(In formula (b1), R ^b0 is an alkyl group or an aromatic group which may have a substituent, and R ^b9 is a hydrogen atom or an alkyl group). The resin composition according to claim 2, wherein R ^b9 in the above formula (b1) is a hydrogen atom. The resin composition according to claim 1, which contains a compound represented by the following formula (b1-2) as the carbonyloxy compound (B1), [Chemical 3]

(In the formula (b1-2), R ^b1 and R ^b2 each independently represent a hydrogen atom, a halogen atom, a hydroxyl group, a mercapto group, a sulfide group, a silyl group, a silanol group, a nitro group, a nitroso group, a sulfinic acid group , sulfo group, sulfonic acid group, phosphino group, phosphinyl group, phosphono group, phosphonic acid group, or organic group; R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 each independently represent a hydrogen atom, a halogen Atom, hydroxyl, mercapto, thioether, silane, silanol, nitro, nitroso, sulfinate, sulfo, sulfonate, phosphino, phosphinyl, phosphono, phosphonate , amine group, ammonium group, or organic group; two or more of R ^b3 , R ^b4 , R ^b5 , R ^b6 , and R ^b7 may also be bonded to form a ring structure, and a bond of a heteroatom may also be contained). The resin composition according to any one of claims 1 to 4, which contains both the above-mentioned carbonyloxy compound (B1) and the above-mentioned basic nitrogen-containing compound (B2). The resin composition according to any one of claims 1 to 4, which contains an imidazole compound as the basic nitrogen-containing compound (B2). The resin composition according to claim 5, which contains an imidazole compound as the basic nitrogen-containing compound (B2). A method of manufacturing a cured product, comprising the steps of: A coating film forming step, coating the resin composition as any one of claims 1 to 7 on the substrate to form a coating film; and In the heating step, the above coating film is heated at 70-550°C. A hardened product obtained by hardening the resin composition according to any one of claims 1 to 7.