CURABLE RESIN COMPOSITION, ADHESIVE AGENT, ADHESIVE FILM, CIRCUIT SUBSTRATE, INTERLAYER INSULATING MATERIAL, AND PRINTED WIRING BOARD

Abstract

A curable resin composition containing: a curable resin; and a curing agent containing an imide oligomer, the imide oligomer containing an aliphatic diamine residue- and/or aliphatic triamine residue-containing imide oligomer that has, in a main chain, an imide skeleton and a substituted or unsubstituted aliphatic diamine residue having a carbon number of 4 or greater and/or a substituted or unsubstituted aliphatic triamine residue having a carbon number of 4 or greater, has a crosslinkable functional group at an end, and has a molecular weight of 5,000 or less. The curable resin composition is excellent in flexibility and processability before curing and excellent in adhesiveness, heat resistance, and dielectric characteristics after curing. An adhesive, an adhesive film, a circuit board, an interlayer insulating material, and a printed wiring board each produced using the curable resin composition are also provided.

Claims

1. A curable resin composition comprising: a curable resin; and a curing agent containing an imide oligomer, the imide oligomer containing an aliphatic diamine residue- and/or aliphatic triamine residue-containing imide oligomer that has, in a main chain, an imide skeleton and a substituted or unsubstituted aliphatic diamine residue having a carbon number of 4 or greater and/or a substituted or unsubstituted aliphatic triamine residue having a carbon number of 4 or greater, has a crosslinkable functional group at an end, and has a molecular weight of 5,000 or less.

2. The curable resin composition according to claim 1, wherein the aliphatic diamine residue and/or the aliphatic triamine residue are/is an aliphatic diamine residue and/or an aliphatic triamine residue derived from a dimer acid and/or a trimer acid.

3. The curable resin composition according to claim 1, wherein the proportion of the aliphatic diamine residue and/or aliphatic triamine residue in the polyvalent amine residues contained in the entire imide oligomer is 5 mol % or more.

4. The curable resin composition according to claim 1, wherein the aliphatic diamine residue- and/or aliphatic triamine residue-containing imide oligomer has a substituted or unsubstituted aromatic tetracarboxylic acid residue in the main chain.

5. The curable resin composition according to claim 1, wherein the crosslinkable functional group is a functional group capable of reacting with an epoxy group.

6. The curable resin composition according to claim 1, wherein the crosslinkable functional group is at least one selected from the group consisting of an acid anhydride group, a phenolic hydroxy group, and an active ester group.

7. The curable resin composition according to claim 1, wherein the aliphatic diamine residue- and/or aliphatic triamine residue-containing imide oligomer has a melting point of 120 C. or lower.

8. The curable resin composition according to claim 1, wherein the amount of the imide oligomer in 100 parts by weight of the total of the curable resin and the curing agent containing an imide oligomer is 5 parts by weight or more and 85 parts by weight or less.

9. The curable resin composition according to claim 1, wherein the curable resin contains an epoxy resin.

10. The curable resin composition according to claim 1, which has a glass transition temperature before curing of 0 C. or higher and lower than 25 C.

11. The curable resin composition according to claim 1, wherein a cured product of the curable resin composition has a glass transition temperature of 100 C. or higher and lower than 250 C.

12. The curable resin composition according to claim 1, wherein a cured product of the curable resin composition has an initial adhesive force to polyimide of 3.4 N/cm or more and the cured product after storage at 200 C. for 100 hours has an adhesive force to polyimide of 3.4 N/cm or more.

13. An adhesive comprising the curable resin composition according to claim 1.

14. An adhesive film produced using the curable resin composition according to claim 1.

15. A circuit board comprising a cured product of the curable resin composition according to claim 1.

16. An interlayer insulating material produced using the curable resin composition according to claim 1.

17. A multilayer printed wiring board comprising: a circuit board; multiple insulating layers provided on the circuit board; and a metal layer provided between the insulating layers, the insulating layers containing a cured product of the interlayer insulating material according to claim 16.

Description

DESCRIPTION OF EMBODIMENTS

[0161] The present invention is described in detail in the following with reference to, but not limited to, examples.

Synthesis Example 1 (Production of Imide Oligomer Composition A)

[0162] An amount of 104 parts by weight of 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride (available from Tokyo Chemical Industry Co., Ltd.) as an aromatic tetracarboxylic acid was dissolved in 300 parts by weight of N-methylpyrrolidone (available from FUJIFILM Wako Pure Chemical Corporation, NMP). To the obtained solution was added a solution obtained by diluting 56.8 parts by weight of Priamine 1073 (available from Croda International plc), which is a dimer diamine, in 100 parts by weight of N-methylpyrrolidone. The mixture was reacted by stirring at 25 C. for two hours to give an amic acid oligomer solution. The N-methylpyrrolidone was removed from the obtained amic acid oligomer solution by pressure reduction, followed by heating at 300 C. for two hours to give an imide oligomer composition A (imidization ratio 93%).

[0163] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition A contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a dimer diamine residue). The imide oligomer composition A had a number average molecular weight of 2,200.

[0164] The imide oligomer composition A had a melting point of 47 C. as measured as an endothermic peak temperature during heating at 10 C./min using a differential scanning calorimeter (available from SII NanoTechnology Inc., EXTEAR DSC6100).

Synthesis Example 2 (Production of Imide Oligomer Composition B)

[0165] An imide oligomer composition B (imidization ratio 95%) was obtained as in Synthesis Example 1 except that instead of 56.8 parts by weight of Priamine 1073 (available from Croda International plc), 61.7 parts by weight of Priamine 1071 (available from Croda International plc), which is a mixture of a dimer diamine and a trimer triamine, was used and that the amount of the 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride added was changed to 115 parts by weight.

[0166] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition B contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (1-1) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a dimer diamine residue). The analyses further showed that the imide oligomer composition B contained an aliphatic triamine residue-containing imide oligomer having a structure represented by the formula (2-1) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a trimer triamine residue). The imide oligomer composition B had a number average molecular weight of 2,780.

[0167] The imide oligomer composition B had a melting point of 52 C. as measured as in Synthesis Example 1.

Synthesis Example 3 (Production of Imide Oligomer Composition C)

[0168] An imide oligomer composition C (imidization ratio 94%) was obtained as in Synthesis Example 1 except that instead of 56.8 parts by weight of Priamine 1073 (available from Croda International plc), 56.1 parts by weight of Priamine 1074 (available from Croda International plc), which is a hydrogenated dimer diamine, was used.

[0169] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition C contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a hydrogenated dimer diamine residue). The imide oligomer composition C had a number average molecular weight of 2,530.

[0170] The imide oligomer composition C had a melting point of 45 C. as measured as in Synthesis Example 1.

Synthesis Example 4 (Production of Imide Oligomer Composition D)

[0171] An imide oligomer composition D (imidization ratio 93%) was obtained as in Synthesis Example 3 except that the amount of Priamine 1074 (available from Croda International plc) added was changed to 28.1 parts by weight, and that 14.6 parts by weight of 1,3-bis(4-aminophenoxy)benzene (available from Seika Corporation, TPE-R) as an aromatic diamine was dissolved in 400 parts by weight of N-methylpyrrolidone along with Priamine 1074. The molar ratio of Priamine 1074 to 1,3-bis(4-aminophenoxy)benzene was as follows: Priamine 1074:1,3-bis(4-aminophenoxy)benzene=1:1.

[0172] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition D contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a hydrogenated dimer diamine residue or a 1,3-bis(4-aminophenoxy)benzene residue, where at least one of the repeating structures is a hydrogenated dimer diamine residue)). The imide oligomer composition D had a number average molecular weight of 2,200.

[0173] The imide oligomer composition D had a melting point of 59 C. as measured as in Synthesis Example 1.

Synthesis Example 5 (Production of Imide Oligomer Composition E)

[0174] An imide oligomer composition E (imidization ratio 93%) was obtained as in Synthesis Example 4 except that the amount of Priamine 1074 (available from Croda International plc) added was changed to 5.6 parts by weight, and that the amount of 1,3-bis(4-aminophenoxy)benzene added was changed to 26.3 parts by weight. The molar ratio of Priamine 1074 to 1,3-bis(4-aminophenoxy)benzene was as follows: Priamine 1074:1,3-bis(4-aminophenoxy)benzene=1:9.

[0175] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition E contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a hydrogenated dimer diamine residue or a 1,3-bis(4-aminophenoxy)benzene residue, where at least one of Bs of the repeating structures is a hydrogenated dimer diamine residue). The imide oligomer composition E had a number average molecular weight of 2,100.

[0176] The imide oligomer composition E had a melting point of 70 C. as measured as in Synthesis Example 1.

Synthesis Example 6 (Production of Imide Oligomer Composition F)

[0177] An imide oligomer composition F (imidization ratio 95%) was obtained as in Synthesis Example 4 except that the amount of Priamine 1074 (available from Croda International plc) added was changed to 2.8 parts by weight, and that the amount of 1,3-bis(4-aminophenoxy)benzene added was changed to 27.8 parts by weight. The molar ratio of Priamine 1074 to 1,3-bis(4-aminophenoxy)benzene was as follows: Priamine 1074:1,3-bis(4-aminophenoxy)benzene=5:95.

[0178] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition F contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a hydrogenated dimer diamine residue or a 1,3-bis(4-aminophenoxy)benzene residue, where at least one of Bs of the repeating structures is a hydrogenated dimer diamine residue). The imide oligomer composition F had a number average molecular weight of 1,980.

[0179] The imide oligomer composition F had a melting point of 92 C. as measured as in Synthesis Example 1.

Synthesis Example 7 (Production of Imide Oligomer Composition G)

[0180] An imide oligomer composition G (imidization ratio 93%) was obtained as in Synthesis Example 1 except that instead of 56.8 parts by weight of Priamine 1073 (available from Croda International plc), 14.5 parts by weight of 3,3-diamino-N-methyldipropylamine (available from Tokyo Chemical Industry Co., Ltd.) was used.

[0181] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition G contained an aliphatic triamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a 3,3-diamino-N-methyldipropylamine residue). The imide oligomer composition G had a number average molecular weight of 1,860.

[0182] The imide oligomer composition G had a melting point of 89 C. as measured as in Synthesis Example 1.

Synthesis Example 8 (Production of Imide Oligomer Composition H)

[0183] An imide oligomer composition H (imidization ratio 94%) was obtained as in Synthesis Example 1 except that instead of 56.8 parts by weight of Priamine 1073 (available from Croda International plc), 14.8 parts by weight of 1,2-bis(2-aminoethoxy)ethane (available from Tokyo Chemical Industry Co., Ltd.) was used.

[0184] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition H contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a 1,2-bis(2-aminoethoxy)ethane residue). The imide oligomer composition H had a number average molecular weight of 1,910.

[0185] The imide oligomer composition H had a melting point of 84 C. as measured as in Synthesis Example 1.

Synthesis Example 9 (Production of Imide Oligomer Composition I)

[0186] An imide oligomer composition I (imidization ratio 95%) was obtained as in Synthesis Example 1 except that instead of 56.8 parts by weight of Priamine 1073 (available from Croda International plc), 14.2 parts by weight of 1,3-bis(aminomethyl)cyclohexane (available from Tokyo Chemical Industry Co., Ltd.) was used.

[0187] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition I contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a 1,3-bis(aminomethyl)cyclohexane residue). The imide oligomer composition I had a number average molecular weight of 1,960.

[0188] The imide oligomer composition I had a melting point of 117 C. as measured as in Synthesis Example 1.

Synthesis Example 10 (Production of Imide Oligomer Composition J)

[0189] An imide oligomer composition J (imidization ratio 94%) was obtained as in Synthesis Example 3 except that instead of 104 parts by weight of 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride, 62.0 parts by weight of 3,4-oxydiphthalic dianhydride (available from Tokyo Chemical Industry Co., Ltd., 3,4-ODPA) was used as an aromatic tetracarboxylic acid.

[0190] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition J contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 3,4-oxydiphthalic acid residue and B is a hydrogenated dimer diamine residue). The imide oligomer composition J had a number average molecular weight of 2,040.

[0191] The imide oligomer composition J had a melting point of 68 C. as measured as in Synthesis Example 1.

Synthesis Example 11 (Production of Imide Oligomer Composition K)

[0192] An amount of 21.8 parts by weight of 3-aminophenol (available from Tokyo Chemical Industry Co., Ltd.) was dissolved in 400 parts by weight of N-methylpyrrolidone (available from FUJIFILM Wako Pure Chemical Corporation, NMP). To the obtained solution was added 157.3 parts by weight of the imide oligomer composition A obtained in Synthesis Example 1. The mixture was reacted by stirring at 25 C. for two hours to give an amic acid oligomer solution. The N-methylpyrrolidone was removed from the obtained amic acid oligomer solution by pressure reduction, followed by heating at 300 C. for two hours to give an imide oligomer composition K (imidization ratio 95%).

[0193] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition K contained an aliphatic diamine residue-containing imide oligomer having, at an end, a structure represented by the formula (1-2) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride residue, B is a dimer diamine residue, and Ar is a group represented by the following formula (9)). The imide oligomer composition K had a number average molecular weight of 2,830.

[0194] The imide oligomer composition K had a melting point of 76 C. as measured as in Synthesis Example 1.

##STR00009##

Synthesis Example 12 (Production of Imide Oligomer Composition L)

[0195] An imide oligomer composition L (imidization ratio 92%) was obtained as in Synthesis Example 1 except that the amount of 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride added was changed to 78 parts by weight.

[0196] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition L contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (3-1) or (3-3) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and B is a dimer diamine residue). The imide oligomer composition L had a number average molecular weight of 5,500.

[0197] The imide oligomer composition L had a melting point of 58 C. as measured as in Synthesis Example 1.

Synthesis Example 13 (Production of Imide Oligomer Composition M)

[0198] An amount of 29.2 parts by weight of 1,3-bis(3-aminophenoxy)benzene (available from Mitsui Fine Chemicals, Inc., APB-N), which is an aromatic diamine, was dissolved in 400 parts by weight of N-methylpyrrolidone (available from FUJIFILM Wako Pure Chemical Corporation, NMP). To the obtained solution was added 104 parts by weight of 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride (available from Tokyo Chemical Industry Co., Ltd.) as an aromatic tetracarboxylic acid. The mixture was reacted by stirring at 25 C. for two hours to give an amic acid oligomer solution. The N-methylpyrrolidone was removed from the obtained amic acid oligomer solution by pressure reduction, followed by heating at 300 C. for two hours to give an imide oligomer composition M (imidization ratio 94%).

[0199] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition M did not contain an aliphatic diamine residue-containing imide oligomer, and contained an aromatic diamine residue-containing imide oligomer. The analyses showed that the aromatic diamine residue-containing imide oligomer had a structure in which the moiety corresponding to A in the formula (3-1) or (3-3) was a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and the moiety corresponding to B was a 1,3-bis(3-aminophenoxy)benzene residue. The imide oligomer composition M had a number average molecular weight of 2,150.

[0200] The imide oligomer composition M had a melting point of 122 C. as measured as in Synthesis Example 1.

Synthesis Example 14 (Production of Imide Oligomer Composition N)

[0201] An imide oligomer composition N (imidization ratio 93%) was obtained as in Synthesis Example 13 except that instead of 29.2 parts by weight of 1,3-bis(3-aminophenoxy)benzene, which is an aromatic diamine, 29.2 parts by weight of 1,3-bis(4-aminophenoxy)benzene (available from Seika Corporation, TPE-R), which is an aromatic diamine, was used.

[0202] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition N did not contain an aliphatic diamine residue-containing imide oligomer, and contained an aromatic diamine residue-containing imide oligomer. The analyses showed that the aromatic diamine residue-containing imide oligomer had a structure in which the moiety corresponding to A in the formula (3-1) or (3-3) was a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue and the moiety corresponding to B was a 1,3-bis(4-aminophenoxy)benzene residue. The imide oligomer composition N had a number average molecular weight of 2,010.

[0203] The imide oligomer composition N had a melting point of 125 C. as measured as in Synthesis Example 1.

Synthesis Example 15 (Production of Imide Oligomer Composition O)

[0204] An amount of 21.8 parts by weight of 3-aminophenol (available from Tokyo Chemical Industry Co., Ltd.) was dissolved in 400 parts by weight of N-methylpyrrolidone (available from FUJIFILM Wako Pure Chemical Corporation, NMP). To the obtained solution was added 143.2 parts by weight of the imide oligomer composition D obtained in Synthesis Example 4. The mixture was reacted by stirring at 25 C. for two hours to give an amic acid oligomer solution. The N-methylpyrrolidone was removed from the obtained amic acid oligomer solution by pressure reduction, followed by heating at 300 C. for two hours to give an imide oligomer composition O (imidization ratio 93%).

[0205] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition O contained an aliphatic diamine residue-containing imide oligomer having, at an end, a structure represented by the formula (1-2) (A is a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue, B is a hydrogenated dimer diamine residue or a 1,3-bis(4-aminophenoxy)benzene residue, and Ar is a group represented by the formula (9)). The imide oligomer composition O had a number average molecular weight of 2,720.

[0206] The imide oligomer composition O had a melting point of 90 C. as measured as in Synthesis Example 1.

Synthesis Example 16 (Production of Imide Oligomer Composition P)

[0207] An amount of 175.5 parts by weight of the imide oligomer composition K obtained in Synthesis Example 11 and 20.3 parts by weight of triethylamine were dissolved in 400 parts by weight of tetrahydrofuran (super dehydrated) (available from FUJIFILM Wako Pure Chemical Corporation, THF). To the obtained solution was added 28.1 parts by weight of benzoylchloride (available from Tokyo Chemical Industry Co., Ltd.), followed by stirring for four hours at 25 C. to allow esterification to proceed. Thereafter, the THF was removed by pressure reduction to give an imide oligomer composition P (imidization ratio 95%).

[0208] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition P contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (1-3) at an end. In the aliphatic diamine residue-containing imide oligomer, in the formula (1-3), R.sup.1 was a phenyl group, R.sup.2 was a group represented by the formula (9), A was a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue, and B was a dimer diamine residue. The imide oligomer composition P had a number average molecular weight of 3,150.

[0209] The imide oligomer composition P had a melting point of 91 C. as measured as in Synthesis Example 1.

Synthesis Example 17 (Production of Imide Oligomer Composition Q)

[0210] An imide oligomer composition Q (imidization ratio 93%) was obtained as in Synthesis Example 16 except that instead of 175.5 parts by weight of the imide oligomer composition K, 161.3 parts by weight of the imide oligomer composition O obtained in Synthesis Example 15 was used.

[0211] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition Q contained an aliphatic diamine residue-containing imide oligomer having a structure represented by the formula (1-3) at an end. In the aliphatic diamine residue-containing imide oligomer, in the formula (1-3), R.sup.1 was a phenyl group, R.sup.2 was a group represented by the formula (9), A was a 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride residue, and B was a hydrogenated dimer diamine residue or a 1,3-bis(4-aminophenoxy)benzene residue. The imide oligomer composition Q had a number average molecular weight of 3,000.

[0212] The imide oligomer composition Q had a melting point of 103 C. as measured as in Synthesis Example 1.

Synthesis Example 18 (Production of Imide Oligomer Composition R)

[0213] An amount of 21.8 parts by weight of 3-aminophenol (available from Tokyo Chemical Industry Co., Ltd.) was dissolved in 400 parts by weight of N-methylpyrrolidone (available from FUJIFILM Wako Pure Chemical Corporation, NMP). To the obtained solution was added 129.7 parts by weight of the imide oligomer composition M obtained in Synthesis Example 13. The mixture was reacted by stirring at 25 C. for two hours to give an amic acid oligomer solution. The N-methylpyrrolidone was removed from the obtained amic acid oligomer solution by pressure reduction, followed by heating at 300 C. for two hours to give an imide oligomer composition R (imidization ratio 94%).

[0214] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition R did not contain an aliphatic diamine residue-containing imide oligomer and contained an aromatic diamine residue-containing imide oligomer. In the aromatic diamine residue-containing imide oligomer, the moiety corresponding to A in the formula (1-2) was a 4,4-(4,4-isopropylidenediphenoxy)diphthalic acid residue, the moiety corresponding to B was a 1,3-bis(3-aminophenoxy)benzene residue, and Ar was a group represented by the formula (9). The imide oligomer composition R had a number average molecular weight of 2,600.

[0215] The imide oligomer composition R had a melting point of 140 C. as measured as in Synthesis Example 1.

Synthesis Example 19 (Production of Imide Oligomer Composition S)

[0216] An amount of 147.9 parts by weight of the imide oligomer composition R obtained in Synthesis Example 18 and 20.3 parts by weight of triethylamine were dissolved in 400 parts by weight of tetrahydrofuran (super dehydrated) (available from FUJIFILM Wako Pure Chemical Corporation, THF). To the obtained solution was added 28.1 parts by weight of benzoylchloride (available from Tokyo Chemical Industry Co., Ltd.), followed by stirring at 25 C. for four hours to allow esterification to proceed. Thereafter, the N-methylpyrrolidone was removed by pressure reduction to give an imide oligomer composition S (imidization ratio 94%).

[0217] .sup.1H-NMR, GPC, and FT-IR analyses showed that the imide oligomer composition S did not contain an aliphatic diamine residue-containing imide oligomer and contained an aromatic diamine residue-containing imide oligomer. In the aromatic diamine residue-containing imide oligomer, the moiety corresponding to R.sup.1 in the formula (1-3) was a phenyl group, the moiety corresponding to R.sup.2 was a group represented by the formula (9), the moiety corresponding to A was a 4,4-(4,4-isopropylidenediphenoxy)diphthalic anhydride residue, and the moiety corresponding to B was a 1,3-bis(3-aminophenoxy)benzene residue. The imide oligomer composition S had a number average molecular weight of 2,920.

[0218] The imide oligomer composition S had a melting point of 155 C. as measured as in Synthesis Example 1.

(Adhesive Film)

Examples 1 to 16 and Comparative Examples 1 to 5

[0219] Curable resin compositions of Examples 1 to 16 and Comparative Examples 1 to 5 were produced in accordance with the formulations shown in Tables 1 to 4.

[0220] Each of the obtained curable resin compositions was applied to a substrate PET film to a thickness of about 20 m and dried to prepare a curable resin composition film.

<Evaluation>

[0221] The curable resin compositions and curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5 were evaluated as follows. Tables 1 to 4 show the results.

(Glass Transition Temperature Before Curing)

[0222] The substrate PET film was removed from each of the curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5. Pieces of the curable resin composition film were laminated using a laminator to prepare a curable resin composition film having a thickness of 400 m. The glass transition temperature of the curable resin composition film was determined as a peak temperature from a tan curve obtained during heating from 0 C. to 300 C. using a dynamic viscoelastometer (available from A & D Company, Limited, RHEOVIBRON DDV-25GP) at a rate of temperature rise of 10 C./min, a frequency of 10 Hz, and a chuck distance of 24 mm.

(Flexibility)

[0223] Each of the curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5 was subjected to a 5-mm-diameter winding test, in which the film was wound around a cylinder having a diameter of 5 mm at 25 C. and examined for the presence or absence of a fracture or chip in the curable resin composition film. Each adhesive film was also subjected to a 180-degree bending test, in which the adhesive film was bent 180 degrees and examined for the presence or absence of a fracture or chip in the curable resin composition film.

[0224] The flexibility was evaluated as 0 (Good) when no fracture or chip was present in both the 5-mm-diameter winding test and the 180-degree bending test, r (Fair) when no fracture or chip was present in the 5-mm-diameter winding test but a fracture or chip was present in the 180-degree bending test, and x (Poor) when a fracture or chip was present in both tests.

(Processability)

[0225] Each of the curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5 was subjected to punching processing at 25 C. using a Thomson blade. The state of the fracture cross section and whether dust had fallen off were examined.

[0226] The processability was evaluated as (Good) when the fracture cross section was smooth and no dust had fallen off, (Fair) when no dust had fallen off but the fracture cross section was not smooth, and x (Poor) when the fracture cross section was not smooth and dust had fallen off.

(Glass Transition Temperature of Cured Product)

[0227] The substrate PET film was removed from each of the curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5. Pieces of the curable resin composition film were laminated using a laminator and heated at 190 C. for one hour to prepare a cured product having a thickness of 400 m. The glass transition temperature of the obtained cured product was determined as a peak temperature from a tan curve obtained during heating from 0 C. to 300 C. using a dynamic viscoelastometer (available from A & D Company, Limited, RHEOVIBRON DDV-25GP) at a rate of temperature rise of 10 C./min, a frequency of 10 Hz, and a chuck distance of 24 mm.

(Adhesiveness)

[0228] The substrate PET film was removed from each of the curable resin compositions obtained in Examples 1 to 16 and Comparative Examples 1 to 5. Polyimide films (available from Du Pont-Toray Co., Ltd., Kapton 200H), each having a thickness of 50 m, were bonded to both surfaces of the adhesive layer using a laminator with heating at 70 C. The laminate was hot pressed under the conditions of 190 C., 3 MPa, and one hour to cure the adhesive layer, and then cut into a specimen having a width of 1 cm. The specimen within 24 hours after the preparation was subjected to a T-peeling using a tensile tester (available from Orientec Co., Ltd., UCT-500) at 25 C. at a peeling speed of 20 mm/min to measure the peel strength. The obtained peel strength was taken as the initial adhesive force. Separately, a specimen prepared in the same manner was stored at 200 C. for 100 hours and then cooled to 25 C. The adhesive force of the specimen within 24 hours after the cooling was measured in the same manner as the initial adhesive force.

[0229] For adhesiveness evaluation, the initial adhesive force and the adhesive force after storage at 200 C. for 100 hours were separately evaluated as (Very Good) when they were 6.0 N/cm or more, (Good) when they were 3.4 N/cm or more and less than 6.0 N/cm, and x (Poor) when they were less than 3.4 N/cm.

(Thermal Decomposition Resistance (5% Weight Reduction Temperature))

[0230] Each of the curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5 was cured by heating at 190 C. for one hour to prepare a cured product.

[0231] The 5% weight reduction temperature of the obtained cured product was measured using a thermogravimetric analyzer (available from Hitachi High-Tech Science Corporation, TG/DTA6200) in a temperature range of 30 C. to 500 C. under the heating conditions of 10 C./min.

(Long-Term Heat Resistance)

[0232] Polyimide films (available from Du Pont-Toray Co., Ltd., Kapton V), each having a thickness of 20 m, were stacked on both surfaces of each of the curable resin composition films obtained in Examples 1 to 16 and Comparative Examples 1 to 5. The curable resin composition film was cured by heating at 190 C. for one hour, followed by heat treatment at 175 C. for 1,000 hours. The laminate of the cured product of the curable resin composition film and the polyimide films after the heat treatment was placed in an arch shape along a cylinder having a diameter of 5 mm or 3 mm at room temperature. The state of the laminate of the curable resin composition film and the polyimide films was then visually observed.

[0233] The long-term heat resistance was evaluated as (Good) when no crack or fracture was observed at all in the laminate placed in an arch shape along the cylinder having a diameter of 3 mm, (Fair) when no crack or fracture was observed in the laminate placed in an arch shape along the cylinder having a diameter of 5 mm, but a crack or a fracture was observed in the laminate placed in an arch shape along the cylinder having a diameter of 3 mm, and x (Poor) when a crack or fracture was observed in the laminate placed in an arch shape along the cylinder having a diameter of 5 mm.

TABLE-US-00001 TABLE 1 Example 1 2 3 4 5 6 7 Composition Curable resin Bisphenol F epoxy resin 100 100 100 100 100 100 100 (parts by (available from DIC Corporation, EPICLON EXA-830CRP) weight) Curing agent Imide oligomer composition A 197 Imide oligomer composition B 216 Imide oligomer composition C 196 Imide oligomer composition D 179 Imide oligomer composition E 166 Imide oligomer composition F 164 Imide oligomer composition G 144 Curing 2, 4-diamino-6-(2-methylimidazolyl-(1))-ethyl-s-triazine 3 3 3 3 3 3 3 accelerator (available from Shikoku Chemicals Corporation, 2MZ-A, melting point 248 C. to 258 C.) Fluidity control Hydrophobic fumed silica 30 30 30 30 30 30 30 agent (available from Tokuyama Corporation, MT-10) Solvent Methyl ethyl ketone 300 300 300 300 300 300 300 (available from FUJIFILM Wako Pure Chemical Corporation, MEK) Amount of imide oligomer in 100 parts by weight of total of curable resin 66 68 66 64 62 62 59 and curing agent containing imide oligomer (parts by weight) Evaluation Before curing Glass transition temperature before curing ( C.) 5 9 6 9 17 23 24 (B stage) Flexibility Processability After curing Glass transition temperature of cured product 128 136 122 177 217 169 204 Adhesiveness Initial adhesive force Adhesive force after storage at 200 C. for 100 hours Thermal decomposition resistance 368 366 372 375 373 375 371 (5% weight reduction temperature ( C.)) Long-term heat resistance

TABLE-US-00002 TABLE 2 Example 8 9 10 11 12 13 Composition Curable resin Bisphenol F epoxy resin 100 100 100 100 100 100 (parts by (available from DIC Corporation, EPICLON EXA-830CRP) weight) Curing agent Imide oligomer composition C 20 5 Imide oligomer composition H 144 Imide oligomer composition I 143 Imide oligomer composition J 143 Imide oligomer composition K 439 Imide oligomer composition N 120 135 Curing 2, 4-diamino-6-(2-methylimidazolyl-(1))-ethyl-s-triazine 3 3 3 3 3 3 accelerator (available from Shikoku Chemicals Corporation, 2MZ-A, melting point 248 C. to 258 C.) Fluidity control Hydrophobic fumed silica 30 30 30 30 30 30 agent (available from Tokuyama Corporation, MT-10) Solvent Methyl ethyl ketone 300 300 300 300 300 300 (available from FUJIFILM Wako Pure Chemical Corporation, MEK) Amount of imide oligomer in 100 parts by weight of total of curable resin 59 59 59 81 17 5 and curing agent containing imide oligomer (parts by weight) Evaluation Before curing Glass transition temperature before curing ( C.) 22 21 10 12 16 24 (B stage) Flexibility Processability After curing Glass transition temperature of cured product 151 167 145 135 151 158 Adhesiveness Initial adhesive force Adhesive force after storage at 200 C. for 100 hours Thermal decomposition resistance 369 381 365 392 380 379 (5% weight reduction temperature ( C.)) Long-term heat resistance

TABLE-US-00003 TABLE 3 Example 14 15 16 Composition Curable resin Bisphenol F epoxy resin 100 100 100 (parts by (available from DIC Corporation, EPICLON EXA-830CRP) weight) Curing agent Imide oligomer composition O 404 Imide oligomer composition P 491 Imide oligomer composition Q 456 Curing 2, 4-diamino-6-(2-methylimidazolyl-(1))-ethyl-s-triazine 3 3 3 accelerator (available from Shikoku Chemicals Corporation, 2MZ-A, melting point 248 C. to 258 C.) Fluidity control Hydrophobic fumed silica 30 30 30 agent (available from Tokuyama Corporation, MT-10) Solvent Methyl ethyl ketone 300 300 300 (available from FUJIFILM Wako Pure Chemical Corporation, MEK) Amount of imide oligomer in 100 parts by weight of total of curable resin 80 83 82 and curing agent containing imide oligomer (parts by weight) Evaluation Before curing Glass transition temperature before curing ( C.) 20 21 23 (B stage) Flexibility Processability After curing Glass transition temperature of cured product 180 138 185 Adhesiveness Initial adhesive force Adhesive force after storage at 200 C. for 100 hours Thermal decomposition resistance (5% weight reduction temperature ( C.)) 402 382 390 Long-term heat resistance

TABLE-US-00004 TABLE 4 Comparative Example 1 2 3 4 5 Composition Curable resin Bisphenol F epoxy resin 100 100 100 100 100 (parts by (available from DIC Corporation, EPICLON EXA-830CRP) weight) Curing agent Imide oligomer composition L 197 Imide oligomer composition M 162 Imide oligomer composition N 162 Imide oligomer composition R 370 Imide oligomer composition S 422 Curing 2, 4-diamino-6-(2-methylimidazolyl-(1))-ethyl-s-triazine 3 3 3 3 3 accelerator (available from Shikoku Chemicals Corporation, 2MZ-A, melting point 248 C. to 258 C.) Fluidity control Hydrophobic fumed silica 30 30 30 30 30 agent (available from Tokuyama Corporation, MT-10) Solvent Methyl ethyl ketone 300 300 300 300 300 (available from FUJIFILM Wako Pure Chemical Corporation, MEK) Amount of imide oligomer in 100 parts by weight of total of curable resin 66 62 62 79 81 and curing agent containing imide oligomer (parts by weight) Evaluation Before curing Glass transition temperature before curing ( C.) 12 26 27 30 35 (B stage) Flexibility x x x x Processability x x x x After curing Glass transition temperature of cured product 125 161 166 167 170 Adhesiveness Initial adhesive force x Adhesive force after storage x at 200 C. for 100 hours Thermal decomposition resistance 365 375 377 390 385 (5% weight reduction temperature ( C.)) Long-term heat resistance x

(Interlayer Insulating Material)

Examples 17 to 26 and Comparative Examples 6 to 8

[0234] The materials in accordance with the formulations shown in Tables 5 and 6 were stirred at 1,200 rpm for four hours to prepare interlayer insulating materials (resin composition vanishes). The compositions in Table 5 and 6 do not include solvents, and show solid components.

[0235] Each of the obtained interlayer insulating materials was applied to the release-treated side of a PET film (available from Toray Industries Inc., XG284, thickness: 25 m) using an applicator. The solvent was evaporated by drying in a gear oven at 100 C. for 2.5 minutes, giving an uncured laminated film including the PET film and a resin film (B-stage film) on the PET film. The resin film had a thickness of 40 m and a residual solvent content of 1.0% by weight or more and 3.0% by weight or less.

<Evaluation>

[0236] The uncured laminated films obtained in Examples 17 to 26 and Comparative Examples 6 to 8 were evaluated as follows. Tables 5 and 6 show the results.

(Flexibility)

[0237] Each of the uncured laminated films obtained in Examples 17 to 26 and Comparative Example 6 to 8 was cut into a rectangular shape with a length of 10 cmand a width of 5 cm. This film was bent 90 degrees or 180 degrees and bent back to its flat form. The state of the film was visually observed. Here, the film is more likely to fracture when bent 180 degrees than when bent 90 degrees.

[0238] The flexibility was evaluated as (Good) when the film did not fracture either when bent 90 degrees or when bent 180 degrees, (Fair) when the film fractured when bent 180 degrees but did not when bent 90 degrees, and x (Poor) when the film fracture both when bent 90 degrees and when bent 180 degrees.

(Dielectric Characteristics)

[0239] Each of the uncured laminated films obtained in Examples 17 to 26 and Comparative Examples 6 to 8 was cut to pieces having a width of 2 mm and a length of 80 mm. Five pieces were stacked together to prepare a stack having a thickness of 200 m. The obtained stack was heated at 190 C. for 90 minutes to prepare a cured article. The dielectric loss tangent of the cured article was measured by the cavity resonance method at 23 C. and a frequency of 1.0 GHz using a cavity resonance perturbation method dielectric constant measuring device CP521 (available from Kanto Electronic Application and Development Inc.) and a network analyzer N5224A PNA (available from available from Keysight Technologies).

[0240] The dielectric characteristics were evaluated as (Very Good) when the dielectric loss tangent was 0.0035 or less, (Good) when the dielectric loss tangent was more than 0.0035 and 0.0040 or less, (Fair) when the dielectric loss tangent was more than 0.0040 and 0.0045 or less, and x (Poor) when the dielectric loss tangent was more than 0.0045.

(Desmear Performance (Residue Removability at Via Bottom))

(1) Lamination and Semi-Curing Treatment

[0241] Both surfaces of a CCL substrate (available from Hitachi Chemical Co., Ltd., E679FG) were immersed in a copper surface roughening agent (available from MEC Co., Ltd., MECetchBOND CZ-8100) to roughen the copper surfaces. Each of the uncured laminated films obtained in Examples 17 to 26 and Comparative Example 6 to 8 was laminated on both surfaces of the CCL substrate from the resin film side using a diaphragm type vacuum laminator (available from Meiki Co., Ltd., MVLP-500). Thus, an uncured laminated sample A was obtained. The lamination was performed by setting the atmospheric pressure to 13 hPa or less by reducing the pressure for 20 seconds, and then pressing the workpiece at 100 C. at a pressure of 0.8 MPa for 20 seconds.

[0242] The PET films were removed from the resin films of the obtained uncured laminated sample A. The resin films were cured at the curing conditions of 170 C. and 30 minutes to give a semi-cured laminated sample.

(2) Formation of Via (Through Hole)

[0243] A via (through hole) having a diameter of 60 m at the upper end and a diameter of 40 m at the lower end (bottom) was formed in the obtained semi-cured laminated sample using a CO.sub.2 laser (available from Hitachi Via Mechanics, Ltd.). Thus, a laminate B was obtained, in which the semi-cured products of the resin films were laminated on the CCL substrate and a via (through hole) was formed in the semi-cured products of the resin films.

(3) Residue Removal Treatment at Via Bottom

(a) Swelling Treatment

[0244] The obtained laminate B was placed in a sweller (available from Atotech Japan K.K., Swelling Dip Securiganth P) at 70 C. and oscillated for 10 minutes. The laminate B was then washed with pure water.

(b) Permanganate Treatment (Roughening Treatment and Desmear Treatment)

[0245] The laminate B after the swelling treatment was put in a potassium permanganate (available from Atotech Japan K.K., Concentrate Compact CP) roughening aqueous solution at 80 C. and oscillated for 30 minutes. Next, the laminate was treated in a cleaning solution (available from Atotech Japan K.K., Reduction Securiganth P) at 25 C. for two minutes, and then washed with pure water to give an evaluation sample 1.

[0246] The via bottom in the evaluation sample 1 was observed with a scanning electron microscope (SEM) and the maximum smear length from the wall surface at the via bottom was measured.

[0247] The desmear performance (residue removability at via bottom) was evaluated as (Very Good) when the maximum smear length was shorter than 2 m, (Good) when the maximum smear length was 2 m or longer and shorter than 2.5 m, (Fair) when the maximum smear length was 2.5 m or longer and shorter than 3 m, and x (Poor) when the maximum smear length was 3 m or longer.

(Plating Adhesiveness)

[0248] A semi-cured laminated sample prepared in the same manner as in (Desmear performance (residue removability at via bottom)) was put in a sweller (aqueous solution prepared from Swelling Dip Securiganth P available from Atotech Japan K.K. and sodium hydroxide (available from FUJIFILM Wako Pure Chemical Corporation)) at 70 C. The sample was oscillated for 10 minutes and then washed with pure water.

[0249] The semi-cured sample after the swelling treatment was put in a sodium permanganate roughening aqueous solution (aqueous solution prepared from Concentrate Compact CP available from Atotech Japan K.K. and sodium hydroxide (available from FUJIFILM Wako Pure Chemical Corporation)) at 80 C. and oscillated for 30 minutes. Subsequently, the sample was washed with a cleaning solution (aqueous solution prepared from Reduction Securiganth P available from Atotech Japan K.K. and sulfuric acid (available from FUJIFILM Wako Pure Chemical Corporation)) at 25 C. for two minutes, then further washed with pure water, whereby a roughened cured product was formed on the CCL substrate.

[0250] The surface of the roughened cured product was treated with an alkali cleaner (Cleaner Securiganth 902 available from Atotech Japan K.K.) at 60 C. for five minutes for degreasing and washing. After the washing, the cured product was treated with a pre-dip solution (available from Atotech Japan K.K., Pre Dip Neoganth B) at 25 C. for two minutes. Thereafter, the cured product was treated with an activator solution (available from Atotech Japan K.K., Activator Neoganth 834) at 40 C. for five minutes, whereby a palladium catalyst was attached.

[0251] Subsequently, the cured product was treated with a reducing solution (available from Atotech Japan K.K., Reducer Neoganth WA) at 30 C. for five minutes and then put in chemical copper solutions (Basic Printganth MSK-DK, Copper Printganth MSK, Stabilizer Printganth MSK, and Reducer Cu, all available from Atotech Japan K.K.). Electroless plating was performed until the plating thickness reached about 0.5 m. After the electroless plating, annealing was performed at 120 C. for 30 minutes to remove the remaining hydrogen gas. All the steps to the electroless plating step were performed while the cured product was oscillated, with the amount of each treatment solution being 2 L on a beaker scale.

[0252] Electroplating was performed on the cured product after the electroless plating. The electroplating was performed using a copper sulfate solution (aqueous solution prepared from copper sulfate pentahydrate (available from FUJIFILM Wako Pure Chemical Corporation), sulfuric acid (available from FUJIFILM Wako Pure Chemical Corporation), Basic Leveler Cupracid HL, and Correction Solution Cupracid GS available from Atotech Japan K.K.), at a current of 0.6 A/cm.sup.2 until the plating thickness reached about 25 m. After the electroplating, the cured product was heated at 190 C. for 90 minutes to be further cured, whereby a cured product having a copper plating layer on its upper surface was obtained.

[0253] In the obtained cured product having the copper plating layer laminated thereon, a cut having a width of 10 mm was made in the surface of the copper plating layer. The adhesion strength (90 peel strength) between the cured product (insulating layer) and the metal layer (copper plating layer) was then measured using a tensile tester (available from Shimadzu Corporation, AG-5000B) at a crosshead speed of 5 mm/min.

[0254] The plating adhesiveness was evaluated as (Very Good) when the peel strength was 0.50 kgf/cm or more, (Good) when the peel strength was 0.45 kgf/cm or more and less than 0.50 kgf/cm, (Fair) when the peel strength was 0.40 kgf/cm or more and less than 0.45 kgf/cm, x (Poor) when the peel strength was less than 0.40 kgf/cm.

TABLE-US-00005 TABLE 5 Comparative Example Example 17 18 19 20 21 22 23 24 6 7 Composition Curable resin Biphenyl epoxy resin 7.8 7.8 7.8 7.8 7.8 7.8 7.8 7.8 7.8 7.8 (parts by (available from Nippon weight) Kayaku Co.,Ltd., NC-3000) Naphthalene epoxy resin 1.3 1.3 12 1.3 1.3 1.3 1.3 1.3 1.3 1.3 (available from DIC Corporation, HP-4032D) Bisphenol F epoxy resin 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 (available from DIC Corporation, EPICLON EXA-830CRP) Naphthalene epoxy resin 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 3.0 (available from Nippon Steel & Sumikin Chemical Co., Ltd., ESN-475V) Curing agent Active ester curing agent 2.5 6.2 8.7 8.7 8.7 8.7 8.7 2.5 12.5 8.7 (available from DIC Corporation, EPICLON EXB-9416-70BK) Phenol curing agent 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 2.3 (available from Meiwa Plastic Industries, Ltd., MEH7851-4H) Imide oligomer composition C 10.0 6.3 3.8 Imide oligomer composition D 3.8 Imide oligomer composition E 3.8 Imide oligomer composition F 3.8 Imide oligomer composition H 3.8 Imide oligomer composition J 10.0 Imide oligomer composition N 3.8 Thermoplastic Phenoxy resin 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 resin (available from Mitsubishi Chemical Corporation, YX6954BH30) Curing 2-phenyl-benzyl-1H-imidazole 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 0.6 accelerator (available from Shikoku Chemicals Corporation, 1B2PZ, melting point 40 C.) Inorganic Silica 70.0 70.0 70.0 70.0 70.0 70.0 70.0 70.0 70.0 70.0 filler (available from Admatechs Company Limited, SC4050-HOA) Amount of imide oligomer in 100 parts by weight of total of curable 35 22 13 13 13 13 13 35 0 13 resin and curing agent containing imide oligomer (parts by weight) Evaluation Before curing Flexibility x x (B stage) After curing Dielectric characteristics x (dielectric loss tangent) Desmear performance x x Plating adhesiveness x

TABLE-US-00006 TABLE 6 Comparative Example Example 25 26 8 Composition Curable resin Biphenyl epoxy resin 7.8 7.8 7.8 (parts by (available from Nippon Kayaku Co., Ltd., NC-3000) weight) Naphthalene epoxy resin 1.3 1.3 1.3 (available from DIC Corporation, HP-4032D) Bisphenol F epoxy resin 1.5 1.5 1.5 (available from DIC Corporation, EPICLON EXA-830CRP) Naphthalene epoxy resin 3.0 3.0 3.0 (available from Nippon Steel & Sumikin Chemical Co., Ltd., ESN-475V) Curing agent Active ester curing agent 8.7 8.7 8.7 (available from DC Corporation, EPICLON EXB-9416-70BK) Phenol curing agent 2.3 2.3 2.3 (available from Meiwa Plastic Industries, Ltd., MEH7851-4H) Imide oligomer composition P 3.8 Imide oligomer composition Q 3.8 Imide oligomer composition S 3.8 Thermoplastic resin Phenoxy resin 1.0 1.0 1.0 (available from Mitsubishi Chemical Corporation, YX6954BH30) Curing accelerator 2-phenyl-benzyl-1H-imidazole 0.6 0.6 0.6 (available from Shikoku Chemicals Corporation, 1B2PZ, melting point 40 C.) Inorganic filler Silica 70.0 70.0 70.0 (available from Admatechs Company Limited, SC4050-HOA) Amount of imide oligomer in 100 parts by weight of total of curable resin and curing agent containing imide oligomer 17 17 17 (parts by weight) Evaluation Before curing Flexibility x (B stage) After curing Dielectric characteristics (dielectric loss tangent) Desmear performance x Plating adhesiveness

INDUSTRIAL APPLICABILITY

[0255] The present invention can provide a curable resin composition excellent in flexibility and processability before curing and excellent in adhesiveness, heat resistance, and dielectric characteristics after curing. The present invention can provide an adhesive, an adhesive film, a circuit board, an interlayer insulating material, and a printed wiring board each produced using the curable resin composition.